Page 24 - Science Course 2 (Book 2)

Mo8-L2: Lesson Review Quiz (True of False)

Direction: On the line before each statement, write T if the statement is true or F if the statement is false

____________ 1. To f nd net force, you must specify the direction in which each force acts.

____________ 2. According to Newton’s f rst law, the motion of an object does not change if the net force
acting on it is zero.

____________ 3. If there were no friction, a moving object would keep moving, even if no other force were
applied to it.

____________ 4. Inertia is two or more forces acting in opposite directions.

Mo8-L2: Lesson Review Quiz (Multiple Choice)

Direction: On the line before each question, write the letter of the correct answer.

5. If one force of 30 N and another force of 85 N result in a net force of 55 N, which term
describes the two forces?
A. negative forces
B. balanced forces
C. unbalanced forces

6. Which term explains why a crash-test dummy lunges forward during a car crash?
A. inertia
B. gravity
C. velocity

7. What happens to an object at rest if balanced forces act upon it?
A. The object remains at rest.
B. The object begins to move at a constant speed.
C. The object begins to move and then slows down.

8. If the reference direction is to the left and a force of 45 N acts to the left while another force
of 65 N acts to the right, how much net force is acting on the object?
A. 20 N
B. –20 N
C. 110 N

Direction: Respond to each statement on the lines provided.

9. Explain why a crash-test dummy falls forward when the car it is in crashes head on or stops suddenly.

10. Predict what would happen to an object that is at rest if balanced forces acted upon it.

16