Worksheet on action-reaction forces and momentum conservation with highlighted answers.

Let’s go step by step through each question using the physics principles given in the box at the top:

> Newton’s Third Law: In a collision, both objects feel forces that are equal in size and opposite in direction.
> → So F₁ = -F₂ (same magnitude, opposite direction)
>
> Impulse = Force × time → Since force is same magnitude and time of contact is same for both objects, impulse is also same magnitude (but opposite direction).
>
> Change in momentum (Δmomentum) = Impulse → So Δp is also same magnitude for both objects.
>
> Acceleration = Force / mass → Same force, but different masses → smaller mass gets bigger acceleration.

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Question 1: Golf club head (0.170 kg) hits golf ball (0.046 kg) at rest

a. Greatest force?
→ Newton’s 3rd law: forces are equal → both the same

b. Greatest impulse?
→ Impulse = F × t → same F, same t → both the same

c. Greatest Δmomentum?
→ Δp = impulse → same → both the same

d. Greatest acceleration?
→ a = F/m → same F, golf ball has smaller mass → golf ball has greater acceleration

✔ Answers for Q1:
a. both the same
b. both the same
c. both the same
d. golf ball

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Question 2: Woman (45 kg) tossed by man (70 kg)

Same logic applies — they push on each other during toss.

a. Force? → Equal and opposite → both the same

b. Impulse? → Same force, same time → both the same

c. Δmomentum? → Equals impulse → both the same

d. Acceleration? → a = F/m → woman has less mass → woman accelerates more

✔ Answers for Q2:
a. both the same
b. both the same
c. both the same
d. woman

*(Note: The pink highlights in your image already show correct answers for this one!)*

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Question 3: Cue ball hits 8-ball (same mass), 8-ball at rest

Even though masses are same, we still apply Newton’s 3rd law.

a. Force? → Always equal in collisions → both the same

b. Impulse? → Same force, same time → both the same

c. Δmomentum? → Equals impulse → both the same

d. Acceleration? → a = F/m → same F, same m → both the same

Wait — let’s double-check part d.

If masses are equal and forces are equal, then yes — accelerations are equal in magnitude (though opposite in direction).

So even though cue ball slows down and 8-ball speeds up, their *magnitudes* of acceleration are the same during contact.

✔ Answers for Q3:
a. both the same
b. both the same
c. both the same
d. both the same

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Question 4: Large truck vs VW Beetle head-on collision

Truck is much heavier than VW.

a. Force? → Newton’s 3rd law → always equal → both the same

b. Impulse? → Same force, same time → both the same

c. Δmomentum? → Equals impulse → both the same

d. Acceleration? → a = F/m → VW has much smaller mass → VW has much larger acceleration

✔ Answers for Q4:
a. both the same
b. both the same
c. both the same
d. VW

*(Again, your pink highlights match these!)*

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## Final Answer:

Question 1:
a. both the same
b. both the same
c. both the same
d. golf ball

Question 2:
a. both the same
b. both the same
c. both the same
d. woman

Question 3:
a. both the same
b. both the same
c. both the same
d. both the same

Question 4:
a. both the same
b. both the same
c. both the same
d. VW