Forces and Motion Five Forces Studied 1. Push 2. Pull 3. Gravity 4. Magnetism 5. Friction.
-
Upload
hector-ferguson -
Category
Documents
-
view
221 -
download
1
Transcript of Forces and Motion Five Forces Studied 1. Push 2. Pull 3. Gravity 4. Magnetism 5. Friction.
Forces and Motion
Force: a push or a pull
The amount of force you have to use to move an object depends on its mass.
Which requires more force?
orBowling ball
Why when you drop something does it always fall down?........
Gravity: force that pulls objects
toward each other
The more mass two objects have, the more gravity pulls them toward each other. Earth has more mass than the moon and so the gravity is stronger on earth.
Weight: measure of the pull of gravity on an object
Magnetism
Opposite poles (north and south) attract
pull
Like poles (south and south or north and north) repel
Iron and Steel are attracted to magnets
Remember the activity of the same ramp, same marble however the floor types are different. Why did the marble travel different distances????
Friction – wood and tile are smoother and thus have less friction and will then allow the marble to travel farther. The carpet is rougher and has more friction, and slows down the marble faster.
Motion: a change in position
Every motion is started by a force and every motion is stopped by a force. A force can also change the position of an object.
Change the direction of a ball by applying another force on the ball.
http://t0.gstatic.com/images?q=tbn:ANd9GcRNd0WZWStr1w2-rJhzDW5-SkDBeLHon4onAvYKFJn8tYPV7xSk
Not all forces stop or start a motion. If one student is pushing on one end of a box and another student is pushing on the opposite end of a box, the forces are balanced and the box doesn’t move. There is no motion.
Equal or Balanced Forces
Speed: Measure of how fast something moves over a certain distance.
To calculate speed: Speed = distance you went/ time it takes to get there
Work: measure of force it takes to move an object a certain distance
Work = force needed to move object (newtons) a certain distance
Pushing against a wall is NOT work.