A ball is dropped from a satellite revolving around the earth at a height of 120 km. The ball will
continue to move with same speed along a straight line tangentially to the satellite at that time.
continue to move with the same speed along the original orbit of satellite
fall down to earth gradually
go far away in space
A rubber ball is dropped from a height of 5 m on a planet where the acceleration due to gravity is not known. On bouncing it rises to 1.8 m. The ball loses its velocity on bouncing by a factor of
16/25
2/5
3/5
9/25
A planet is moving in elliptical orbit around the sun. If T, U, E and L stand for its kinetic energy, gravitational potential energy, total energy and magnitude of angular momentum about the centre of force, which of the following is correct?
T is conserved
U is always positive
E is always negative
L is conserved but direction of vector L changes continuously
The escape velocity from the surface of the earth is ve. The escape velocity from the surface of a planet whose mass and radius are three times those of the earth, will be
ve
3ve
9ve
1/3ve