A ball is dropped from a satellite revolving round the earth at a height of 120 km. The ball will

Solution
The orbital speed of satellite is independent of mass of satellite,so the ball will behave as a satellite and will continue to move with the same speed in the original orbit.
A man waves his arms while walking. This is to

Solution
g′=g−ω2Rcos2λ.
A missile is launched with a velocity less than escape velocity. The sum of its kinetic and potential energies is
There is no atmosphere on the moon because

SolutionV_{esc}=2gR−−−−√
, where R is radius of the planet.Hence escape velocity is independent of m.

Solution
Since, T=ιg√2π
but inside the satellite g=0 So, T=∞
If the earth stops rotating about its axis, the acceleration due to gravity will remain unchanged at

SolutionThe period of revolution of the satellite must be exactly one day,or 86400s. The centripetal acceleration of the satellite must be 4π^{2}r/T^{2}, the gravitational field must be g=g_{0}(r_{0}/r)^{2}. In free fall,a=g, so
r=(9.8m/s2)(6.4m×10−6m)2(86400s)24π2−−−−−−−−−−−−−−−−−−−−−√3=4.23×10^{7}m
To get the altitude, subtract the radius of the earth. The satellite must be at an altitude of 36000 km.