Newton& #039;s Laws - Free Printable

Let’s go step by step through each question on the worksheet. We’re using Newton’s Second Law:
Force = mass × acceleration → F = m × a
So, acceleration = Force ÷ mass → a = F/m

We’ll calculate acceleration for each diagram and compare.

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Question 1:

Diagrams A and B both show a 5 kg object.

- Diagram A: Two forces — 30 N to the right, 20 N to the left → Net force = 30 - 20 = 10 N to the right
- Diagram B: Two forces — 30 N to the right, 10 N to the left → Net force = 30 - 10 = 20 N to the right

a. In which diagram are the forces balanced?
→ Balanced means net force = 0. Neither is zero. So neither diagram has balanced forces.

Wait — let me double-check. The question says “in which diagram are the forces balanced?” If both have unbalanced forces, then answer is “none”. But maybe I misread?

Looking again:

Diagram A: 30N right, 20N left → net 10N right → unbalanced
Diagram B: 30N right, 10N left → net 20N right → unbalanced

So correct answer: Neither diagram has balanced forces.

But sometimes worksheets expect you to say “none” or “not applicable”. Let’s keep going.

b. What will happen to the object in each diagram? Why?

→ Since both have net force to the right, both objects will accelerate to the right.
Diagram B has larger net force (20N vs 10N), so it accelerates more.

Acceleration for A: a = F/m = 10N / 5kg = 2 m/s²
Acceleration for B: a = 20N / 5kg = 4 m/s²

So both move right, but B moves faster (accelerates more).

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Question 2:

Both diagrams show circular objects with two horizontal forces.

Diagram A: 40 N right, 10 kg mass
Diagram B: 80 N right, 5 kg mass

a. What factor is different in diagrams A and B? What factor is the same?

Different:
- Force applied (40N vs 80N)
- Mass (10kg vs 5kg)

Same:
- Direction of force (both to the right)
- Type of motion (linear acceleration along one axis)
Actually, looking closely — both have only one force shown? Wait no — in diagram A, there’s an arrow labeled 40N pointing right, and another arrow pointing left? No — wait, re-examining:

In diagram A: Only one force shown? Actually, looking at the image description — in Q2, diagram A shows a circle with 40N arrow to the right, and below it says “10 kg”. Diagram B shows 80N arrow to the right, and “5 kg” below.

Wait — actually, in the original problem statement, for Q2, it might be that each diagram has only ONE force acting? Because no opposing force is drawn.

Check the user’s image description: For Q2, it says:

“2. a. What factor is different in diagrams A and B? What factor is the same?
b. Which object will have the greater acceleration? Why?”

And diagrams:
A: ← 40 N → [circle] 10 kg
B: ← 80 N → [circle] 5 kg

Wait — actually, looking back at the text provided:
For Q2:
"A: ← 40 N → [object] 10 kg" — this likely means 40 N force to the right? Or is the arrow direction indicating force direction?

Standard convention: Arrow points in direction of force.

In diagram A: Arrow labeled 40 N pointing to the right → force = 40 N right, mass = 10 kg
In diagram B: Arrow labeled 80 N pointing to the right → force = 80 N right, mass = 5 kg

No other forces shown → so net force equals the single force shown.

So:

a. Different factors:
- Magnitude of force (40N vs 80N)
- Mass (10kg vs 5kg)

Same factors:
- Direction of force (both to the right)
- Number of forces (one force each)
- Object shape? Not relevant. Probably just: direction and type of force application.

But simplest answer:
Different: force size and mass
Same: direction of force (or perhaps “both have a single horizontal force”)

b. Which object has greater acceleration?

Calculate:

A: a = F/m = 40N / 10kg = 4 m/s²
B: a = 80N / 5kg = 16 m/s²

So B has greater acceleration because although mass is smaller, force is much larger — and since a = F/m, B’s ratio is bigger.

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Question 3:

Diagrams C and D: both 3 kg objects.

C: 60 N to the left
D: 30 N to the left

a. How do diagrams C and D compare?

Both have same mass (3 kg), same direction of force (left), but different force magnitudes (60N vs 30N).

b. Which object will have greater acceleration? Why?

C: a = 60N / 3kg = 20 m/s² left
D: a = 30N / 3kg = 10 m/s² left

So C has greater acceleration because same mass, but larger force → acceleration proportional to force when mass constant.

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Question 4:

Diagrams A and B: both have 1 kg objects.

A: 5 N to the right
B: 5 N to the left

a. What factors are different in diagrams A and B?

Only difference: direction of force (right vs left). Force magnitude same (5N), mass same (1kg).

b. Which object will have greater acceleration? Why?

Acceleration magnitude:
A: a = 5N / 1kg = 5 m/s² right
B: a = 5N / 1kg = 5 m/s² left

So same magnitude of acceleration, just opposite directions.

Therefore, neither has “greater” acceleration if we mean magnitude. But if the question implies vector comparison, still — same size.

Typically in such contexts, “greater acceleration” refers to magnitude unless specified otherwise.

So answer: They have the same acceleration magnitude, just in opposite directions.

But let’s check wording: “Which object will have the greater acceleration?”

Since acceleration is a vector, technically they are different vectors. But in middle school physics, often “greater” means larger magnitude.

Given that, and since |a| is same, answer should be: They have the same acceleration magnitude.

But maybe the worksheet expects: “Same acceleration, different direction.”

I think safest: state that magnitudes are equal.

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Now compiling final answers clearly.

Final Answer:

1.
a. Neither diagram has balanced forces.
b. Both objects accelerate to the right. Object in diagram B accelerates more (4 m/s²) than object in diagram A (2 m/s²) because it has a larger net force (20 N vs 10 N) and same mass.

2.
a. Different: force magnitude (40 N vs 80 N) and mass (10 kg vs 5 kg). Same: direction of force (both to the right).
b. Object in diagram B has greater acceleration (16 m/s²) than object in diagram A (4 m/s²) because its force-to-mass ratio is larger (80/5 > 40/10).

3.
a. Both have same mass (3 kg) and force direction (left), but different force magnitudes (60 N vs 30 N).
b. Object in diagram C has greater acceleration (20 m/s²) than object in diagram D (10 m/s²) because it experiences a larger force with the same mass.

4.
a. The only difference is the direction of the force (right in A, left in B); force magnitude (5 N) and mass (1 kg) are the same.
b. Both objects have the same acceleration magnitude (5 m/s²), but in opposite directions. So neither has “greater” acceleration in terms of size.