An infinity number of point masses each equal to m are placed at x = 1, x = 2, x = 4, x = 8, ..... What is the total gravitational potential at x - 0?
-Gm
-2Gm
-4Gm
-8 Gm
The radius of earth is 6400 km and the value of g is 10m/s2 . If the weight of 5km body on the equator becomes zero, then the angular speed of earth will be :
A satellite moves eastwards very near the surface of the earth in the equatorial plane of the earth with speed v0. Another satellite moves at the same height with the same speed in the equatorial plane but westwards. If R is the radius of the earth and ω be its angular speed about its own axis, then the difference in the two time period as observed on the earth will be approximately equal to :
The weight of a body at earth surface is 700 g wt. What will be its weight on a planet whose mass is 1/7 that of earth and radius half that of earth?
300 g-wt
200 g-wt
400 g-wt
57.1 g-wt
A satellite is revolving round the earth. Its K.E is Ek. How much would it be made so that the satellite may escape out of the gravitational field of earth?
2Ek
3Ek
Ek/2
Infinite
Suppose the gravitational force varies inversely as the nth power of distance. Then the time period of a planet in circular orbit of radius R around the sun will be proportional to :
Rn
The escape velocity for a body projected vertically upwards from the surface of earth is 11km/s. If the body is projected at an angle of 45° with the vertical, the escape velocity will be :
11km/s
11/√2 m/s
11√2 km/s
22 km/s
Energy required to move a body of mass m from an orbit of radius 2R to 3R is :
If the radius of the earth decreases by 10%, the mass remaining unchanged, what will happen to the acceleration due to gravity?
Decreases by 19%
Increases by 19%
Decreases by more than 19%
Increases by more than 19%
The kinetic energy needed to project a body of mass m from the earth's surface (radius R) to infinity is :
mgR
2mgR