Page 31 - Science Course 2 (Book 2)

Mo8-L3: Lesson Review Quiz (True or False)

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

1. Only unbalanced forces change an object’s velocity.

2. Centripetal force causes an object in circular motion to move along a straight path.

3. Unbalanced forces can cause an object in motion to accelerate.

4. If the direction of the net force acting on an object is opposite to the direction of movement,
the object will speed up.

Mo8-L3: Lesson Review Quiz (Multiple Choice)

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

5. A ball held in a person’s hand does not move, even though gravity is acting on it because
A. the force of gravity creates a net unbalanced force.
B. the force of gravity is not strong enough to move the ball.
C. the force of gravity is balanced by the force exerted by the hand.

6. Which situation is NOT the result of an unbalanced force acting on an object?
A. an object speeds up
B. an object maintains speed
C. an object changes direction

7. How does inertia act on an object that is moving in a circle?
A. It causes the object to speed up as it moves.
B. It causes the object to move along a straight path.
C. It directs the object toward the center of the curve.

Direction: Respond to each statement on the lines provided.

5. Balanced forces act on a ball that is being held above the ground in someone’s hand.
Explain why these forces on the ball are balanced.

6. Calculate the acceleration of an object with a mass of 2 kg that has a force of 30 N acting on it using
Newton’s second law of motion. Explain your calculations.

7. State some of the ways that unbalanced forces acting on an object can affect the motion of that object.

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