Motion. Speed and Velocity An object is moving if its position changes against some background that...

22
Motion

Transcript of Motion. Speed and Velocity An object is moving if its position changes against some background that...

Page 1: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Motion

Page 2: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

An object is moving if its position changes against some background that stays the same◦Reference frame

Page 3: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

Speed describes how fast an object moves

How do we determine speed?

Page 4: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

To find speed, you must measure two quantities: distance traveled and the time it takes to travel that distance

Page 5: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

When an object covers equal distances in equal amounts of time, it is moving at a constant speed

Page 6: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

The relationship between speed, distance, and time can be investigated by plotting a distance-time graph

Page 7: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

Most objects do not move at constant speed

Average speed is the distance covered divided by the time it takes to travel that distance

Page 8: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

Velocity describes both speed and direction

Page 9: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

1. 110m/72s=1.5 m/s toward shore

Page 10: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

1. 110m/72s=1.5 m/s toward shore2. 38m/1.7s= 22m/s toward first base

Page 11: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

1. 110m/72s=1.5 m/s toward shore2. 38m/1.7s= 22m/s toward first base3. D=vt (12km/h)(5h)=60km(1000m/km)=

6x104 m

Page 12: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

1. 110m/72s=1.5 m/s toward shore2. 38m/1.7s= 22m/s toward first base3. D=vt (12km/h)(5h)=60km(1000m/km)=

6x104 m4. T=d/v (2.6km)(1000m/km)/(28m/s)=93s

Page 13: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Speed and Velocity

The velocity of an object changes if its speed or direction changes or both change

Page 14: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

An object with more momentum would be more difficult to stop◦Depends on both its

velocity and its mass

Page 15: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

For an object moving in a straight line:◦Momentum=

mass x velocity P=mv

Page 16: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

Momentum, like velocity, has direction◦Momentum has

same direction as velocity

If an object is not moving, its momentum is zero

Page 17: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

1.a. (75kg)(16m/s)=1200kg m/s forward

Page 18: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

1.a. (75kg)(16m/s)=1200kg m/s forward b. (135kg)(16.2m/s)=2190kg m/s north

Page 19: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

1.a. (75kg)(16m/s)=1200kg m/s forward b. (135kg)(16.2m/s)=2190kg m/s north c. (5kg)72m/s)=360kg m/s eastward

Page 20: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

1.a. (75kg)(16m/s)=1200kg m/s forward b. (135kg)(16.2m/s)=2190kg m/s north c. (5kg)72m/s)=360kg m/s eastward d. (.8kg)(6.5m/s)=5kg m/s to the left

Page 21: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

1.a. (75kg)(16m/s)=1200kg m/s forward b. (135kg)(16.2m/s)=2190kg m/s north c. (5kg)72m/s)=360kg m/s eastward d. (.8kg)(6.5m/s)=5kg m/s to the left e. (48.5kg)(0m/s)=0kg m/s

Page 22: Motion. Speed and Velocity An object is moving if its position changes against some background that stays the same ◦Reference frame.

Momentum

The total amount of momentum in a system is conserved