Chapter 8 – Work and Energy 8. 1 Work pp. 188-192.
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Transcript of Chapter 8 – Work and Energy 8. 1 Work pp. 188-192.
Chapter 8 ndash Work and Chapter 8 ndash Work and EnergyEnergy
8 1 Work8 1 Work
pp 188-192pp 188-192
TERMS TO LEARNTERMS TO LEARN
Work ndash Work ndash the action that results when a the action that results when a force causes an object to move in the force causes an object to move in the direction of the force being applieddirection of the force being applied
Joule ndash Joule ndash the SI unit of workthe SI unit of work
JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE
An English An English physicistphysicist
The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim
81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance
You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter
WORKWORK
The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object
movemove in the direction of the forcein the direction of the force
ANDAND only when the force is being applied only when the force is being applied
to the objectto the object
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
TERMS TO LEARNTERMS TO LEARN
Work ndash Work ndash the action that results when a the action that results when a force causes an object to move in the force causes an object to move in the direction of the force being applieddirection of the force being applied
Joule ndash Joule ndash the SI unit of workthe SI unit of work
JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE
An English An English physicistphysicist
The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim
81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance
You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter
WORKWORK
The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object
movemove in the direction of the forcein the direction of the force
ANDAND only when the force is being applied only when the force is being applied
to the objectto the object
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
JAMES PRESCOTT JOULEJAMES PRESCOTT JOULE
An English An English physicistphysicist
The SI unit of The SI unit of work (work (the joulethe joule) ) is named after is named after himhim
81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance
You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter
WORKWORK
The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object
movemove in the direction of the forcein the direction of the force
ANDAND only when the force is being applied only when the force is being applied
to the objectto the object
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 WorkIn science In science workwork is a is a form of energy you either form of energy you either use or get when a force use or get when a force is applied over a is applied over a distancedistance
You do 1 You do 1 joulejoule of work if of work if you push with a force of you push with a force of 1 newton for a distance 1 newton for a distance of 1 meterof 1 meter
WORKWORK
The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object
movemove in the direction of the forcein the direction of the force
ANDAND only when the force is being applied only when the force is being applied
to the objectto the object
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
WORKWORK
The scientific meaning of work is that The scientific meaning of work is that work is done on an objectwork is done on an object only when a force makes an object only when a force makes an object
movemove in the direction of the forcein the direction of the force
ANDAND only when the force is being applied only when the force is being applied
to the objectto the object
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
CALCULATING WORKCALCULATING WORK
The equation you use to calculate The equation you use to calculate work iswork is
work = force work = force times distancetimes distance
W = F times dW = F times d
The SI unit of work is the The SI unit of work is the joule (J)joule (J)
1 J = 1 N 1 J = 1 N m m
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 WorkWhen thinking about work remember that work When thinking about work remember that work is is done by forces that cause movementdone by forces that cause movement If nothing moves (distance is zero) then If nothing moves (distance is zero) then no work no work is doneis done
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 Work
W = F x dDistance (m)
Force (N)
Work (joules)
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work and energy81 Work and energyDoing work always means Doing work always means transferringtransferring energy energy The energy may be transferred to the object you The energy may be transferred to the object you apply the force to or it may go somewhere elseapply the force to or it may go somewhere else
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work and energy81 Work and energy
You can do work to You can do work to increase an objectrsquos increase an objectrsquos potential energypotential energy
Then the Then the potential potential energy can be energy can be converted to kinetic converted to kinetic energyenergy
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 WorkIf force is equivalent to the weight If force is equivalent to the weight of the object in newtons andof the object in newtons andheight (height (hh) is equivalent to ) is equivalent to distance (distance (dd) ) Then multiplying the weight by Then multiplying the weight by height gives you the amount of height gives you the amount of work the object can accomplish work the object can accomplish as it moves down (as it moves down (as well as its as well as its potential energypotential energy))
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 WorkForce A does no work Force A does no work because because it does not it does not cause cause the block to movethe block to moveForce B is applied at an Force B is applied at an angle to the direction of angle to the direction of motion so only motion so only partpart of force of force B does workB does workThe most effective force to The most effective force to move the block is move the block is force Cforce C
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
How much work is done by a person who How much work is done by a person who pulls a cart with a force of 50 newtons if pulls a cart with a force of 50 newtons if the cart moves 20 meters in the direction the cart moves 20 meters in the direction of the forceof the force
Solving ProblemsSolving Problems
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
11 Looking forLooking for helliphellipwork done by personwork done by person
22 Given Given helliphellipforce = 50 N (forward) force = 50 N (forward) helliphellipdistance = 20 mdistance = 20 m
33 Relationships Relationships Work = force x distanceWork = force x distance
44 SolutionSolution 50 N times 20 m = 50 N times 20 m = 1000 joules1000 joules
Solving ProblemsSolving Problems
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork
81 Work81 Work
Complete Skill Sheet 81 Complete Skill Sheet 81 WorkWork