Gravitation Worksheet-8

Gravitation Worksheet-8

 

  1. State the kepler’s law which is represented by the relation r3 ∝ T2.

 

  1. Which of the Kepler's laws of planetary motion led Newton to establish the inverse-square rule for gravitational force between two bodies ?

 

  1. Name the property of earth which is responsible for extremely small acceleration being produced in it as a result of attraction by other small objects.

 

  1. What is the acceleration produced in a freely falling body of mass 10 kg ? (Neglect air resistance)

 

  1. When an object is dropped from a height, it accelerates and falls down. Name the force which accelerates the object.

 

  1. Give the formula for the gravitational force F between two bodies of masses M and m kept at a distance d from each other.

 

  1. What force is responsible for the earth revolving round the sun ?

 

  1. What name has been given to the force with which two objects lying apart attract each other ?

 

  1. What type of force is involved in the formation of tides in the sea?

 

  1. Which force is responsible for holding the solar system together ?

 

  1. What is the weight of a 1 kilogram mass on the earth ? (g = 9.8 m/s2).

 

  1. On what factor/factors does the weight of a body depend ?

 

  1. As the altitude of a body increases, do the weight and mass both vary ?

 

  1. If the same body is taken to places having different gravitational field strength, then what will vary: its weight or mass ?

 

  1. If the mass of an object be 5 kg, what is its weight ? (g = 9.8 m/s2).

 

  1. The weight of a body is 50 N. What is its mass ? (g = 9.8 m/s2).

 

  1. A body has a weight of 10 kg on the surface of earth. What will be its weight when taken to the centre of the earth ?

 

  1. Write down the weight of a 50 kg mass on the earth. (g = 9.8 m/s2).

 

  1. If the weight of a body on the earth is 6 N, what will it be on the moon ?

 

  1. Explain what is meant by the equation:

         

where the symbols have their usual meanings.

 

Answer:

  1. The cube of the mean distance of a planet from the sun is directly proportional to the square of time it takes to move around the sun

 

  1. Kepler’s third law

 

  1. Extremely large mass of earth

 

  1. 9.8 m/s2

 

  1. Gravitational force (of earth)

 

 

  1. Gravitational force

 

  1. Gravitational force

 

  1. Gravitational force exerted mainly by the moon.

 

  1. Gravitational force (of the sun)

 

  1. 9.8 N

 

  1. Mass of the body as W = mg

 

  1. Weight varies; Mass does not vary

 

  1. Weight

 

  1. 49 N

W = mg

 

  1. W = mg  5.102 kg

 

 

  1. Using w = mg       

490 N

 

  1. About 1 N