### Eamcet - Physics - Gravitation

Degenerate electron pressure will not be sufficient to prevent core collapse of 'white dwarf' if its mass becomes n times of solar mass. Value of n is:

A.  0.5

B.  0.8

C.  1

D.  1.4

If the earth suddenly stops rotating, the value of g at equator would :

A.  decrease

B.  remain unchanged

C.  increase

D.  become zero

The mass of a planet is half that of the earth and the radius of the planet is one-fourth that of earth. If we plan to send an artificial satellite from the planet, the escape velocity will be, (escape velocity on earth ve =11 km- s-1)

A.  11 km-s-1

B.  5.5 km-s-1

C.  15.5 km-s-1

D.  7.78 km-s-1

Two satellites A and B go around the earth in a circular orbits at a height of RA and RB respectively from the surface of the earth. Assume the earth to be a uniform sphere of radius RE. The ratio of magnitudes of the velocities of the statellites VA/VB =

A.  √RB/RA

B.  RB + RE/(RA +RE)

C.  √(RB + RE)/(RA + RE)

D.  √RA /RB

A body is projected vertically upwards from the surface of the earth with a velocity equal to half the escape velocity. If R is the radius of the earth, maximum height attained by the body from the surface of the earth is

A.  R/6

B.  R/3

C.  2R/3

D.  R

A gun is aimed at a target in line with its barrel. The target is released and allowed to fall under gravity, at the instant, the gun is fired. The bullet will :

A.  pass above the target

B.  pass below the target

C.  hit the target

D.  certainly hit the target

The coefficient of kinetic friction between a body and the surface of an inclined plane at 450 is 0.5. If g = 9.8 ms-2,the acceleration of the body down the inclined plane, in ms-2is:

A.  4.9/√2

B.  4.9

C.   4.9√2

D.  19.6√2