SUBJECT : PHYSICS - SSA Punjab

UNIT- IIILAWS OF MOTION2 marks questions1. What is inertia? Why do we call the Newton’s first law as the law ofinertia?2. Is force needed to keep a body moving with uniform velocity?3. State Newton’s law of motion.4. Define linear momentum.If the rate of change of momentum of a body is10kgms -1 . What is the force acting on the body?5. Why do we fall forward, when a moving bus suddenly stops? Explain.6. No force is required to move a body with a constant velocity. Explain.7. We hit the carpet with a stick to remove dust particles. Explain.8. Why a horse cannot pull a cart and run in the empty space?9. Why an athlete runs some steps before taking the jump?10. What is the importance of Newton’s second law of motion? Explain.11. Bodies of larger mass need greater initial effort to put them in motion.Why?12. It is easier to pull than to push a body. Explain.13. Show that it is easier to pull a lawn roller than to push it.14. A cricketer player lowers his hands while taking a catch. Why?15. Why wheels are provided with mudguards?16. Why shockers are used in cars and scooters?17. Why does a heavy rifle not kick as strongly as a light rifle using samecartridges?18. A stone when thrown on a glass window smashes the window pane topieces, but a bullet from the gun passes through making a clean hole.Why?19. Why chinaware and glassware are wrapped in paper or straw piecesbefore packing?20. Action and reaction are equal and opposite. Why cannot they cancel eachother?21. Friction is self adjusting force. Why?22. What is relation between coefficient of friction and angle of friction?23. What is relation between coefficient of friction and angle of repose?24. Why is friction a non-conservative force?25. If the coefficient of friction is 1, calculate the angle of friction?26. Why wheels are made circular?27. Why do we slip on a rainy day?12