NEWTONS FIRST LAW OF MOTION 09 FORCE AND LAWS OF MOTION Class 9th Science (Physics) (Practice Sheet) 1 What is another name for Newton's First Law of Motion? A. Law of Acceleration B. Law of Inertia C. Law of Interaction D. Law of Gravity 2 Which of the following best describes Newton's First Law of Motion? A. An object at rest tends to stay at rest, and an object in motion tends to stay in motion with the same speed and in the same direction, unless acted upon by an external force. B. The force applied to an object is equal to the rate of change of its velocity over time. C. The gravitational force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. D. The momentum of an object is directly proportional to the force applied to it and inversely proportional to its acceleration. 3 Which of the following scenarios best illustrates Newton's First Law of Motion? A. A soccer ball rolling to a stop after being kicked. B. A car accelerating from 0 to 60 mph in 5 seconds. C. A book sliding off a table and falling to the floor. D. A hockey puck sliding on an ice rink at a constant speed. 4 According to Newton's First Law of Motion, what happens to the motion of an object when no external force acts on it? A. It comes to a complete stop. B. It continues moving with constant speed. C. Its speed increases continuously. D. Its direction of motion changes randomly. 5 Which of the following is an example of inertia? A. A car accelerating around a corner. B. A ball rolling down a hill. C. A person feeling a push when a car suddenly stops. D. A passenger moving forward when a bus suddenly starts. 6 Calculate the net external force to keep a body of 500kg in motion. The constant velocity is 10m8 . 7 A spaceship of 1000kg travels in a vacuum at a uniform speed of 500ms. Calculate the net external force, not considering the gravitational forces. 8 The constant speed of a moving airplane is 650mph. The constant speed of a car is 650mph. Which vehicle has the larger acceleration? 9 The mass of a skydiver is 92kg and has reached the ultimate velocity at 52m/s. Calculate the force of wind resistance. Page 1 Email: Phone No: Website:
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