Unit 3 Newton S Laws

AMS 6th

Unit 2 – Newton’s Laws Name: ______Test Study Guide

Definitions:

1. Acceleration

2. Force

3. Free fall

4. Inertia

5. Mass

6. Newton’s 1st Law

7. Newton’s 2nd Law

8. Newton’s 3rd Law

9. Terminal Speed

Review Questions:

Motion Review 1. The mass of an object on the Earth is the ______as on the moon.

2. If the net force on an object moving at constant speed is zero, then its acceleration is ______.

3. For an object at rest, the net force acting on the object is ______.

4. If a box is being pulled with a constant speed across the floor with a force of 3 N, the force of

friction between the box and the floor is______. AMS 6th

Newton’s 1 st Law

1. With the tablecloth trick, what keeps the dishes on the table?

2. An electric toy car is tied to a pole with a string. If the string is cut, what direction will the toy car move in?

3. Inertia is measured by this property of matter: ______

4. In order to accelerate an object, you must overcome its ______.

5. The inertia of an object on the moon is ______to the inertia of the object on the Earth.

6. A box is being pulled on a wagon moving at a speed of 10 m/s. Neglecting air resistance, the speed of the box when it falls off the wagon is:

7. A clown is juggling balls while riding a unicycle at a constant velocity. If the clown drops a ball, will it fall: a. Ahead of him b. Behind him c. Exactly below him

Newton’s 2 nd Law:

1. Suppose you apply the same force (1 N) to two different carts, one with a mass of 1 kg and the other with a mass of 2 kg. Which cart will accelerate more?

2. The force of gravity between the moon and an object near its surface is much smaller than the force of gravity on the Earth. A bowling ball with a mass of 7.51 kg is pulled downward with a force of 12.2 N. What is the acceleration of the falling bowling ball on the moon?

3. If an object’s mass does not change but the force acting on the object is doubles, then the acceleration of the object is: a) doubled b) halved c) quadrupled AMS 6th 4. If an object’s mass is doubled but the force acting on the object is the same, then the acceleration of the object is: a) doubled b) halved c) quadrupled

5. If an object is falling with a force of 20 N (W) and has an air-resistance (R) of 10 N, what is the magnitude of the force acting on the object?

6. In a vacuum, a brick and a feather are dropped at the same time. Which will hit the bottom first? Why?

7. Air resistance, which is a force of friction, depends on ______and ______.

8. The terminal velocity occurs when the air resistance increases, the net force becomes 0 and acceleration stops. After this point, the speed of the object is ______.

9. Why will an object in free- fall not experience terminal velocity as it falls?

10. A small sheet of paper is placed beneath a book and both the book and the paper are dropped at the same time. They accelerate equally because the book pushes down on the paper. Now the paper is placed on top of the book (without sticking out beyond the edge of the book) and they are dropped at the same time. Which has the greater acceleration? Explain your answer. AMS 6th

Newton’s 3 rd Law:

1. An interaction consists of ______and ______forces.

2. For every action, there is an ______and ______reaction.

3. If the action force is a man pulling on a spring, then the reaction force is a ______pulling on ______.

4. A car hits a wall with a force of 100 N. The force of the wall hitting the car is ______N.

5. A falling boulder experiences a force which is responsible for its acceleration. What is the reaction to this force? Can you rewrite this question in terms of an action-reaction pair.