Download Forces Cause Changes in motion

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Forces Cause Changes in Motion
1. Obtain a spring scale and pull it with one newton of force. Does one newton seem like much force?
2. Obtain a cart and determine its mass.
3. Place two 500 gram masses in your cart. Attach a spring scale to the cart's string. Be sure that the spring
scale is zeroed.
a. Predict what the cart's motion will be like if you were to pull it with a constant force of 0.5 Newton.
b. Pull the cart across the floor with a constant force of 0.5 newton. Describe the motion of the cart.
c. Predict what the cart's motion will be like if you were to pull it with a constant force of 1.0 newton
instead of 0.5 newton.
d. Pull the cart across the floor with a constant force of 1.0 newton. Compare the motion of the cart to its
motion when it was pulled by 0.5 newton.
e. Predict what the cart's motion will be like if you were to pull it with a constant force of 1.5 newtons.
f. Pull the cart across the floor with a constant force of 1.5 newton. Compare the motion of the cart to its
motion when it was pulled by 0.5 newton.
4. True or False. “If you pull a cart with a constant force, then it will go at a constant speed.”
5. True or False. “The greater the force acting on an object, the faster the object’s motion is changed.”
The NET FORCE acting on an object is the sum of all the force acting on it. The net force on an object is zero
if
the forces acting on it tend to cancel each other out. For instance, as you sit in your chair, the earth’s gravity is
pulling you down, but the chair is pushing you up with an equal amount of force. This makes the net force on
you zero.
6. Give an example of an object which is speeding up and has a net force acting on it.
7. Give an example of an object which is speeding up, but has no net force acting on it.
8. Give an example of an object which is slowing down and has a net force acting on it.
9. Give an example of an object which is slowing down, but has no net force acting on it.
10. Give an example of an object which is changing its direction and has a net force acting on it.
11. Give an example of an object which is changing its direction, but has no net force acting on it.
12. Give an example of an object which is at rest and has a net force acting on it.
13. Give an example of an object which is at rest and has no net force acting on it.
14. True or False. “If an object is going at a constant speed and in a constant direction, then the forces acting on
it cancel each other out.”
15. True or False. “If an object’s speed and/or direction is changing, then the forces acting on it do not cancel
each other out.”