Force and Laws of Motion (बल तथा गति के नियम) Ch(8) Practice Quiz in Hindi Part – 2 || Class 9 Science Practice Quizzes in English Posted on February 28, 2025February 28, 2025 by Anshul Gupta0% 0 votes, 0 avg 0 Force and Laws of Motion (बल तथा गति के नियम) Ch(8)Practice Quiz in Hindi Part – 2 || Class 9 Science Practice Quizzes in English 1 / 201. What is the first law of motion mathematically stated from? A. Both a and b B. Mathematical expression for the third law of motion C. None of the above D. Mathematical expression for the second law of motion Explanation: The first law of motion can be mathematically stated from the mathematical expression for the second law of motion. 2 / 202. What is the force necessary to change the momentum of an object dependent on? A. Time rate at which the momentum is changed B. None of the above C. Time during which the momentum is changed only D. Magnitude of the momentum only Explanation: The force necessary to change the momentum of an object depends on the time rate at which the momentum is changed. 3 / 203. What is the relationship between the acceleration of an object and the force applied to it? A. None of the above B. The acceleration of an object is directly proportional to the force applied to it. C. The acceleration of an object is independent of the force applied to it. D. The acceleration of an object is inversely proportional to the force applied to it. Explanation: The acceleration of an object is directly proportional to the force applied to it. 4 / 204. What is the purpose of making athletes fall on a cushioned bed or a sand bed in a high jump athletic event? A. To increase the time of the athlete's fall to stop after making the jump B. To decrease the force on the athlete C. To decrease the time of the athlete's fall to stop after making the jump D. To increase the force on the athlete Explanation: The purpose of making athletes fall on a cushioned bed or a sand bed in a high jump athletic event is to increase the time of the athlete’s fall to stop after making the jump. 5 / 205. What is the negative sign in the force exerted by the brakes on a motorcar indicative of? A. The force exerted by the brakes is in the same direction as the direction of motion of the motorcar. B. The force exerted by the brakes is opposite to the direction of motion of the motorcar. C. The force exerted by the brakes is independent of the direction of motion of the motorcar. D. None of the above Explanation: The negative sign in the force exerted by the brakes on a motorcar indicates that the force exerted by the brakes is opposite to the direction of motion of the motorcar.6 / 206. What is the second law of motion? A. The rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force. B. None of the above C. An object remains in a state of rest or of uniform motion in a straight line unless compelled to change that state by an applied force. D. To every action, there is an equal and opposite reaction and they act on two different bodies. Explanation: The second law of motion states that the rate of change of momentum of an object is proportional to the applied unbalanced force in the direction of force. 7 / 207. What is the condition for an object to remain at rest? A. u = a B. u = 0 C. u = v D. None of the above Explanation: The condition for an object to remain at rest is u = 0. 8 / 208. What is the relationship between the acceleration of an object and its mass? A. None of the above B. The acceleration of an object is inversely proportional to its mass. C. The acceleration of an object is independent of its mass. D. The acceleration of an object is directly proportional to its mass. Explanation: The acceleration of an object is inversely proportional to its mass. 9 / 209. What is the friction force that will be exerted on the cabinet if we intend to move a wooden cabinet across a floor at a constant velocity using a horizontal force of 200 N? A. 200 N B. -100 N C. 100 N D. -200 N Explanation: The friction force that will be exerted on the cabinet is 200 N. Since the cabinet is moving at a constant velocity, the net force acting on it is zero. Therefore, the friction force must be equal and opposite to the applied force.10 / 2010. What is the net accelerating force and the acceleration of the train if an 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track? The engine exerts a force of 40000 N and the track offers a friction force of 5000 N. A. -35000 N, -3.5 m/s^2 B. -45000 N, -4.5 m/s^2 C. 45000 N, 4.5 m/s^2 D. 35000 N, 3.5 m/s^2 Explanation: The net accelerating force is 35000 N and the acceleration of the train is 3.5 m/s^2.11 / 2011. What is the change of momentum of an object determined by? A. Magnitude of the force and time during which the force is exerted B. None of the above C. Time during which the force is exerted only D. Magnitude of the force only Explanation: The change of momentum of an object is determined by the magnitude of the force and the time during which the force is exerted. 12 / 2012. What is the mathematical formulation of the second law of motion? A. F = v/t B. F = mv C. F = m/a D. F = ma Explanation: The mathematical formulation of the second law of motion is F = ma. 13 / 2013. What is the second law of motion often seen in action in? A. Pushing a box B. All of the above C. Kicking a football D. Catching a fast-moving cricket ball Explanation: The second law of motion is often seen in action in catching a fast-moving cricket ball. 14 / 2014. What is the SI unit of force? A. Joule B. Meter per second squared C. Kilogram D. Newton Explanation: The SI unit of force is Newton (N). 15 / 2015. What must be the force between the vehicle and the road if an automobile vehicle has a mass of 1500 kg and is to be stopped with a negative acceleration of 1.7 m/s^2? A. 2550 N B. 1700 N C. -1700 N D. -2550 N Explanation: The force between the vehicle and the road must be -2550 N. The negative sign indicates that the force acts in the opposite direction to the motion of the vehicle.16 / 2016. What is the impact produced by an object dependent on? A. Its mass and acceleration B. Its velocity and acceleration C. Its mass, velocity, and acceleration D. Its mass and velocity Explanation: The impact produced by an object is dependent on its mass and velocity. 17 / 2017. What is the condition for an object to continue moving with uniform velocity? A. F = ma B. F = 0 C. F = m/a D. None of the above Explanation: The condition for an object to continue moving with uniform velocity is F = 0. 18 / 2018. What is the momentum of an object of mass m, moving with a velocity v? A. mv B. 1/2 mv^2 C. mv^2 D. (mv)^2 Explanation: The momentum of an object of mass m, moving with a velocity v is mv.19 / 2019. What is the force of friction between a stone and the ice if the stone of 1 kg is thrown with a velocity of 20 m/s across the frozen surface of a lake and comes to rest after traveling a distance of 50 m? A. 4 N B. -2 N C. 2 N D. -4 N Explanation: The force of friction between the stone and the ice is -4 N. The negative sign indicates that the force of friction acts in the opposite direction to the motion of the stone.20 / 2020. What is the quantity that combines an object’s mass and velocity? A. Force B. Inertia C. Acceleration D. Momentum Explanation: The quantity that combines an object’s mass and velocity is momentum. Please insert your information to see your ranking अपनी Ranking जानने के लिए कृपया अपनी जानकारी भरे NamePhone Number Your score isThe average score is 0% 0% Restart quiz Category: Class 9 Science Quizzes in English