A planet is moving in an 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
If the gravitational force between two object were proportional to 1/R (and not as 1/R2), where R is separation between them, then a particle in circular orbit under such a force would have its orbital speed v proportional to
1/R2
R0
R
1/R
The distance of two planets from the sun are 1013 and 1012 m respectively. The ratio of time periods of these two planets is
100
10√10
√10
A second pendulum is mounted in a rocket. Its period of oscillation decreases when the rocket
Comes down with uniform acceleration
Moves round the earth in a geostationary orbit
Moves up with a uniform velocity
Moves up with uniform acceleration
The escape velocity from earth is 11.2 km/s. If a body is to be projected in a direction making an angle 45o to the vertical, then the escape velocity is
11.2 × 2 km/s
11.2 km/s
11.2/√2 km/s
11.2√2 km/s
The period of revolution of planet A around the sun is 8 times that of B. The distance of A from the sun is how many times greater than that of B from the sun?
5
4
3
2
Two spheres of masses m and M are situated in air and the gravitational force between them is F. The space around the masses is now filled with a liquid of specific gravity 3. The gravitational force will now be
F/3
F/9
3F
F
The acceleration due to gravity on the planet A is 9 times the acceleration due to gravity on planet B. A man jumps to a height of 2m on the surface of A. What is the height of jump by the same person on the planet B?
6 m
2/3 m
2/9 m
18 m
The largest and the shortest distance of the earth from the sun are r1 and r2. Its distance from the sun when it is perpendicular to the major axis of the orbit drawn from the sun is
The escape velocity of a sphere of mass m is given by (G = universal gravitational constant, Me = mass of earth and Re = radius of earth)
