10

MAXIMUM TIME: 35 MINUTES

MAXIMUM MARKS: 20 marks

1.  Give the S.I. unit of G and its value.      1

2.  g=GM/R², what does these symbols denote?      1

3.  When a ball is let free fall from the top of building. What is the acceleration and what its sign?      1

4.  A ball is projected vertically upwards with an initial velocity ‘u goes to a maximum height ‘h’ before touching the ground. What is the value of ‘h’ ?      2

5.  How is the weight of an object related to its mass?      2

6.  The mass of the body on earth is 60kg, what is its weight on the earth and on moon.      2

7.  The mass of earth is 6x10²⁴ kg and that of the moon is 7.4x 10²²kg. If the distance between the earth and the moon is 3.84x10⁵km. Calculate the force exerted by the earth and the moon.      2

     G=6.67x10^-11 Nm² kg^-2

8.  Calculate the value of ‘g’ acceleration due to gravity.      1

9.  Gibe difference between ‘g’ and ‘G’      2

10.  If ball is thrown up in the sky, what will happen to its value of ‘g’?      1

11.  Derive the formula for the universal law of gravitation.      2

12.  A car falls of a ledge and drops to the ground in 0.5 s. Let g= 10 ms^-2

      a. What is its speed on touching the ground?

      b. What is its average speed during 0.5s?

      c. How high is the ledge from the ground?      3