The kinetic energy needed to project a body of mass $m$ from the earth's surface (radius $R$) to infinity is
$\frac{{mgR}}{2}$
$2mgR$
$mgR$
$\frac{{mgR}}{4}$
The mass of planet is $\frac{1}{9}$ of the mass of the earth and its radius is half that of the earth. If a body weight $9\,N$ on the earth. Its weight on the planet would be ........ $N$
When a body is taken from pole to the equator its weight
The escape velocity from a planet is $V_e.$ A tunnel is dug along the diameter of the planet and a small body dropped into it. The speed of the body at the centre of the planet will be
The orbital angular momentum of a satellite revolving at a distance $r$ from the centre is $L.$ If the distance is increased to $4r$ then the new angular momentum will be
A geostationary satellite is orbiting the earth at a height of $6\, R$ from the earth’s surface ($R$ is the earth’s radius ). What is the period of rotation of another satellite at a height of $2.5\, R$ from the earth’s surface