The figure shows elliptical orbit of a planet m about the sun S. The shaded area SCD is twice the shaded area SAB. If t1 is the time for the planet to move from C to D and t2 is the time to move from A to B, then
t1 > t2
t1 = 4t2
t1 = 2t2
t1 = t2
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
The escape velocity of a body on the surface of the earth is 11.2 km/s. If the earth's mass increases to twice its present value and the radius of the earth becomes half, the escape velocity would become
44.8 km/s
22.4 km/s
11.2 km/s (remain unchanged)
5.6 km/s
Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g', then
g' = 3g
g' = 9 g
g' = 27g
A satellite A of mass m is at a distance r from the surface of the earth. Another satellite B of mass 2m is at a distance of 2r from the earth's surface. Their time periods are in the ratio of
1 : 2
1 : 16
1 : 32
1 : 2 √2
Escape velocity from earth is 11.2 km/s. Another planet of same mass has radius 1/4 times that of earth. What is the escape velocity from another planet ?
11.2 km/s
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
Two satellites of earth, S1 and S2 , are moving in the same orbit. The mass of S1 is four times the mass of S2 . Which one of the following statement is true ?
The time period of S1 is four times that of S2.
The potential energies of earth and satellite in the two cases are equal.
S1 and S2 are moving with the same time period.
The kinetic energies of the two satellites are equal.
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.
A body attains a height equal to the radius of the earth. The velocity of the body with which it was projected is
