INTRODUCTION ABOUT FORCE 09 FORCE AND LAWS OF MOTION Class 9th Science (Physics) (Practice Sheet) 1 What is force? A. A push or pull on an object. B. The speed of an object. C. The color of an object. D. The temperature of an object. 2 Which of the following is NOT a contact force? A. Frictional force B. Gravitational force C. Mechanical force D. Spring force 3 The SI unit of force is: A. Kilogram B. Newton C. Joule D. Meter 4 According to Newton's first law of motion, an object will remain at rest or in uniform motion unless acted upon by a net external force. This property is also known as: A. Law of inertia B. Law of acceleration C. Law of momentum D. Law of interaction 5 Which of the following is an example of a non-contact force? A. Frictional force B. Frictional force C. Magnetic force D. Normal force 6 Suppose one have a box of mass 2kg. How much force should be applied to the box so that it should travel with the acceleration of 8m/s2 ? 7 A ball of mass 2kg is moving with the initial speed of 5m/s and then suddenly comes to rest in 0.02 sec. Calculate the force that changed the state of the moving ball. 8 If a block is placed on a wooden table such that on one side of the block, a force of 100 N is being applied, and on the other side, a force of 40 N is being applied. Will the block move? If yes, then specify the magnitude of the force and the direction of the force. 9 A 13kg block slides along the floor with a constant velocity. What is the net force on the block? 10 The two balls with masses as 10kg and 20kg respectively. Their respective accelerations are 20m/s2 and 40m/s2 . Find the ratio of their respective forces. Page 1 Email: Phone No: Website:
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