Newtons laws of motion worksheet - Free Printable

Let’s go through each question one by one, step by step.

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Question 6:
> According to Newton’s third law of motion, what does every action have?

Newton’s third law says: “For every action, there is an equal and opposite reaction.”
That means if you push something, it pushes back on you with the same force but in the opposite direction.
Looking at the options:
- a. No reaction → Wrong. There’s always a reaction.
- b. An equal and opposite reaction → Correct! That’s exactly what the law says.
- c. The same reaction → Vague and not accurate — it must be *opposite* too.
- d. A larger reaction → No, it’s equal, not larger.

✔ So the answer is b.

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Question 7:
> If you place a book on your desk, it will remain at rest on your desk unless a force causes it to move. Which of Newton’s laws does the example help explain?

This is describing inertia — objects stay still (or keep moving) unless acted on by a force.
That’s Newton’s first law of motion.

Options:
- a. Gravitational force → Not a law of motion, and not the main idea here.
- b. First law → Yes! This matches perfectly.
- c. Second law → That’s about F = ma — force, mass, acceleration. Not this.
- d. Third law → Action-reaction pairs. Not relevant here.

✔ Answer is b.

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Question 8:
> What is the force of an object equal according to Newton’s second law of motion?

Newton’s second law: Force = Mass × Acceleration → F = m × a

So we’re looking for “mass times acceleration”.

Options:
- a. Height + speed → Nope, unrelated.
- b. Weight ÷ acceleration → Weight is already a force; dividing by acceleration doesn’t give force.
- c. Mass × acceleration → YES! Exactly F = ma.
- d. Width × speed → Nonsense in physics terms.

✔ Answer is c.

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Question 9:
> If you and a friend hold a book, a pencil, a paper clip and a crayon at the same height in the air, and drop them all, which item will hit the ground with the greatest force?

When things fall, they accelerate due to gravity at the same rate (ignoring air resistance). But the *force* when they hit depends on their mass — because Force = mass × acceleration (F = ma). Since acceleration (gravity) is the same for all, the heavier object hits with more force.

Which is heaviest? The book.

Paper clip and crayon are light. Pencil is medium. Book is clearly the heaviest.

✔ Answer is a. The book

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Question 10:
> If you drop an object, it will fall directly to the ground because of...

Why do things fall down? Because of gravity — Earth pulls everything toward its center.

Options:
- a. Friction → Slows things down, doesn’t make them fall.
- b. Gravity → YES! That’s why things fall.
- c. Inertia → Keeps things moving or still — not why they fall.
- d. Work → Energy transfer — not the cause of falling.

✔ Answer is b. Gravity

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Final Answer:
6. b
7. b
8. c
9. a
10. b