Physics Gravitation Test 2 Online MCQs

1. The radius of earth is about 6400 km and that of mass is about 3200 km. The mass if the earth is about 10 times of the mass. The object weighs 200 N on earth surface, then its weight on the surface of mars will be

2. Gravitational mass is proportional to the gravitational:

3. Hubble’s law is related with

4. The ratio of the radii of two planets r₁ and r₂ is k. The ratio of acceleration due to gravity on them is r. then the ratio of the escape velocities from them, will be:

5. The angular speed of earth in rad/s, so that bodies on equator may appear weightless is: [Use g = 10 m/s² and the radius of earth = 6.4 x 10³ km]

6. A long straight wire or radius a carries a steady current I. The current is uniformly distributed across its cross section. The ratio of the magnetic field at a/2 and 2a is

7. A geostationary satellite is orbiting the earth at a height of 6 R from the earth’s surface (R is the earth’s radius). What is the period of rotation of another satellite at a height of 2.5 R from the earth’s surface

8. The earth rotates about the sun in an elliptical orbit as shown in figure. At which point its velocity will be maximum?

9. The velocity with which a projectile must be fired so that it escapes earth’s gravitation does not depend on:

10. Escape velocity of a body when projected from the earth’s surface is 11.2 km/sec. If it is projected at an angle of 50° from the horizontal, then escape velocity is:

11. If the mass of moon is M/81, where M is the mass of earth, find the distance of the point from the moon, where gravitational field due to earth the moon cancel each other. Given that distance between earth and moon is 60R where R is the radius of earth

12. Height of geostationary satellite is

13. A satellite is launched into a circular orbit of radius R around the earth. While a second satellite launched into an orbit of radius 1.01R. The period of the second satellite is longer than the first one by approximately

14. The value of acceleration due to gravity, at earth surface is g. Its value at the center of the earth, which we assume as a sphere of radius R and of uniform mass density, will be:

15. Knowing that the mass of the moon is 1/81 times that if earth and its radius is 1/4 the radius of earth. If the escape velocity at the surface of the earth is 11.2 km/sec, then the value of escape velocity at the surface of the moon is