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d. it escapes out of the earth's field.

6.
Two planets A and B have the same material density. If the radius of A is twice
that of B, Then the ratio of the escape velocity vA/vB is

a. 2

b. √2
c. 1/√2

d. 1/2

7.
A rocket is fired with a velocity 0.6 times the escape velocity on the surface of
earth. How high will it go from the surface?

a. 74/28 R

b. 45/28 R

c. 12/28 R
d. 72/28 R

8.
Out of the following, the only correct statement about satellites is ;
a. A satellite can not move in a stable orbit in a plane passing through
the earth centre

b. Geostationary satellites are launched in the equatorial plane

c. We can use just one geostationary satellite for global communication
around the globe

d. The speed of a satellite increases with an increase in the radius of its
orbit.

9.
Time period of a simple pendulum inside a satellite orbiting earth is
a. Zero

b.
c. T

d. 2 T

10.
The kinetic energy of a satellite in its orbit around the earth is E. What should be
the kinetic energy of the satellite so as to enable it escape from the gravitational
pull of the earth?

a. 4 E

b. 2 E

c. 2 E

d. E