📚 Part A: Multiple Choice (Questions 1-8)

Circle the best answer for each question.

✏️ Part B: Short Answer & Calculations (Questions 9-16)

Phase 1: _________________________ Description: _________________________________

Phase 2: _________________________ Description: _________________________________

📋 Answer Key

Part A - Multiple Choice:

1. C (Third law - action-reaction pairs)

2. B (Point where all mass appears concentrated)

3. C (Third class - effort between fulcrum and load)

4. B (Momentum = mv, so doubles when v doubles)

5. C (Body mass doesn't affect stability directly)

6. C (Horizontal velocity constant without air resistance)

7. B (Torque = rotational effect of force)

8. C (Chemical energy in muscles → kinetic → potential energy)

Part B - Short Answer & Calculations:

9. p = mv = 70 × 8 = 560 kg⋅m/s

10. Impulse = mΔv = 0.16 × (40-0) = 6.4 N⋅s

11. Treaded soles increase friction between shoe and ground, providing better grip and preventing slipping during movement.

12. Wider stance increases base of support, making the gymnast more stable by making it harder for centre of mass to move outside the base.

13. Stance phase: foot in contact with ground, supporting body weight. Swing phase: foot off ground, moving forward for next step.

14. At start: high PE, zero KE. During fall: PE converts to KE. At water entry: minimum PE, maximum KE.

15. Leaning creates centripetal force needed for circular motion and keeps centre of mass over base of support during the turn.

16. Torque = Force × distance = 300 N × 0.8 m = 240 N⋅m