Physics Worksheet

💪 Work

Chapter: Mechanics · Level ★★☆ · Time: 30 min

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After this worksheet you can

Understand: Work DefinitionUnderstand: Positive, Negative, and Zero WorkUnderstand: Units of WorkUnderstand: Work Done Against Gravity

📚 Quick Recap

In physics, 'work' has a precise meaning: force applied over a distance — simply pushing hard without moving anything technically accomplishes no work at all.

🧠 Section A · Concept Check ● BEGINNER 4 × 1 = 4

1A 25 N force pushes an object 6m in the same direction. Find work done.

2Find the work to lift a 8 kg object 3m (g=10).

3A 30 N force is applied at 45° to motion, moving an object 5m (cos(45°)~0.707). Find work done.

4Friction of 10 N acts opposite to a 4m displacement. Find the work done by friction.

🧮 Section B · Problem Solving ● INTERMEDIATE 4 × 3 = 12

5Why is no work done when carrying a bag at constant height while walking horizontally?

6A 50 N force pushes an object 10m in the same direction. Find work done.

7What condition makes the work done by a force exactly zero (assuming the object does move)?

8Find the work to lift a 12 kg object 4m (g=10).

🚀 Section C · Challenge ● CHALLENGE 2 × 2 = 4

9A crate is pushed 3m with 40 N force at 0°, then work-energy theorem applies. If it starts at rest, find its final KE (assuming this is the only force).

10Why can work done be negative?

💭 Reflection — the most useful thing I learned:

A ___/4 B ___/12 C ___/4 Total ___/20 Teacher's Signature Parent's Signature

✂ answer key — fold or cut before handing out

1 = 150 J 2 = 240 J 3 = ≈106 J 4 = -40 J (negative since it opposes motion) | 5 = The force (upward, to support the bag's weight) is perpendicular to the horizontal displacement, so cos(90°)=0 6 = 500 J 7 = When the force is perpendicular to the displacement 8 = 480 J | 9 = 120 J 10 = When the force has a component opposite to the direction of displacement, like friction acting against motion