UNIVERSAL LAW OF GRAVITATION 10 GRAVITATION Class 9th Science (Physics) (Practice Sheet) 1 What is the force of attraction between two objects with masses of 5 kg and 8 kg separated by a distance of 10 meters? (Gravitational constant, G = 6. 67 × 10 −11 N m2/kg2) A. 3.335 × 10-10 N B. 3.335 × 10-9 N C. 3.335 × 10-8 N D. 3.335 × 10-7 N 2 What happens to the gravitational force between two objects if the distance between them is doubled while keeping the masses constant? A. It becomes one-fourth of the original force B. It becomes half of the original force C. It remains the same D. It becomes four times the original force 3 On the Moon, the acceleration due to gravity is about 1.6 m/s2. If an object is dropped from a height of 80 meters on the Moon, how long will it take to reach the surface? A. 5 seconds B. 10 seconds C. 10 seconds D. 4 seconds 4 Which of the following quantities does NOT affect the gravitational force between two objects? A. Mass of Object 1 B. Mass of Object 2 C. Distance between the objects D. Charge of Object 1 5 What is the weight of an object with a mass of 20 kg on Earth? (Acceleration due to gravity on Earth, g = 9.8m/s2 A. 200 N B. 98 N C. 20 N D. 180 N 6 State the Universal Law of Gravitation stated by Newton and mention the formula. 7 At the centre of the Earth why does a body have no weight? 8 Calculate the Gravitational Force between two objects separated by a distance of 5m with masses of 3kgs and 4kgs. 9 What is the gravitational force if the mass of two bodies is 80kg and 200kg and they are separated by a distance of 6m. 10 Two objects of masses m1 and m2 when separated by distance 'r' in air attract each other with force 4N. How is magnitude of force changed when the masses of the object are reduced to one-half? Page 1 Email: Phone No: Website:
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