Class 9 Practice Level 2 – Force and Laws of Motion set – 2 Leave a Comment / By anushka kumari / July 8, 2024 Class 9 Practice Level 2 – Force and Laws of Motion set - 2 Total questions: 25 1. A 5 kg object is subjected to a net force of 15 N. What is the acceleration of the object? 2 m/s² 3 m/s² 4 m/s² 5 m/s² None 2. Which of the following scenarios best illustrates Newton's First Law of Motion? A car accelerating on a highway A book remaining at rest on a table A satellite orbiting the Earth A ball thrown in the air None 3. A truck of mass 2000 kg is moving with a velocity of 15 m/s. What is its momentum? 15,000 kg·m/s 20,000 kg·m/s 25,000 kg·m/s 30,000 kg·m/s None 4. When an object moves on a surface, the type of friction it experiences is: Static friction Sliding friction Rolling friction Fluid friction None 5. If the force acting on a 6 kg object is increased from 12 N to 24 N, what happens to the acceleration? It doubles It halves It remains the same It becomes zero None 6. An impulse of 50 Ns is applied to a 10 kg object initially at rest. What will be its velocity? 2 m/s 5 m/s 10 m/s 20 m/s None 7. Which force acts towards the center of the circle in uniform circular motion? Centrifugal force Centripetal force Gravitational force 'Frictional Force' None 8. When a bird pushes down on the air with its wings, the air pushes the bird up. This is an example of? Newton's First Law Newton's Second Law Newton's Third Law Law of Conservation of Momentum None 9. The gravitational force between two objects is directly proportional to? The square of the distance between them The product of their masses The difference in their velocities The sum of their volumes None 10. Work done by a constant force is zero when the displacement is? Along the direction of force Opposite to the direction of force Perpendicular to the direction of force Parallel to the direction of force None 11. Which of Newton’s laws is also known as the law of inertia? First Law Second Law Third Law None of the above None 12. A 10 N force and a 20 N force act in opposite directions on an object. The net force is: 10 N 20 N 30 N 5 N None 13. The acceleration due to gravity on the surface of the Earth is approximately: 8.9 m/s² 9.8 m/s² 10.8 m/s² 11.8 m/s² None 14. Which law explains why it is harder to push a loaded wheelbarrow than an empty one? Newton's First Law Newton's Second Law Newton's Third Law Law of Gravitation None 15. The tension in a rope is greatest when: The rope is slack The rope is horizontal The rope is vertical The rope is at an angle None 16. If the velocity of an object changes from 15 m/s to 30 m/s in 3 seconds, what is its acceleration? 5 m/s² 10 m/s² 15 m/s² 20 m/s² None 17. According to the work-energy theorem, the work done on an object is equal to its change in: Kinetic energy Potential energy Thermal energy Chemical energy None 18. What force is needed to give a 10 kg mass an acceleration of 2 m/s²? 5 N 10 N 20 N 25 N None 19. Which of the following is an example of Newton’s Third Law? A rocket launching A car braking A book on a table A ball thrown upwards None 20. The frictional force is highest when: The surfaces in contact are smooth The surfaces in contact are rough The object is in motion The object is at rest None 21. Two forces, 5 N and 12 N, act on an object at right angles. The resultant force is: 7 N 12 N 13 N 17 N None 22. Work is done when a force: Acts perpendicular to displacement Acts parallel to displacement Does not cause displacement Changes direction None 23. Which of the following quantities is conserved in an isolated system? Force Mass Momentum Energy None 24. Kinetic friction acts between: Surfaces at rest Surfaces in relative motion Smooth surfaces only Rough surfaces only None 25. What provides the centripetal force for a satellite orbiting the Earth? Frictional force Tension force Gravitational force Electrostatic force None 1 out of 25 Time's up