21. | F (a) 10 (b) 10 (c) 10 (d) 10 |

22. | The value of ‘g’ at a particular point is 9.8 m/sec (a) 9.8 m/sec (b) 4.9 m/sec (c) 19.6 m/sec (d) 2.45 m/sec |

23. | The planet mercury is revolving in an elliptical orbit around the sun as shown in figure. The kinetic energy of mercury will be greater at
(a) A (b) B (c) C (d) D |

24. | The orbit velocity of an artificial satellite in a circular orbit just above the earth’s surface is v. For a satellite orbiting at an altitude of half of the earth’s radius, the orbital velocity is (a) (b) (c) (d) |

25. | If the change in the value of g at the height h above the surface of the earth is the same as at a depth x below it, then (both x and h being much smaller than the radius of the earth) (a) x = h (b) x = 2 h (c) x = (d) x = h |

Answer

21. Ans.: (c)

22. Ans.: (a)

23. Ans.: (a)

24. Ans.: (c)

25. Ans.: (b)