Physics Exercises/Gravity

1. If ve and vo denotes the escape velocity and orbital velocity of a satellite corresponding to a circular orbit of radius R, then
   1. $v_{e}=v_{o}$
   2. $v_{e}=1.74\times v_{o}$
   3. $v_{e}=v_{o}/1.74$
   4. $v_{e}$ and $v_{o}$ are not related
2. the orbital traced by planet around a star is in general
   1. a circle
   2. an ellipse
   3. a parabola
   4. a straight line
3. the period of a satellite in a circular orbit of radius R is T.What is the period of another satellite in a circular orbit of radius 4R
   1. 4T
   2. T/8
   3. T/4
   4. 8T
4. A satellite is moving around the earth in a circular orbit.Which of the following statement is correct
   1. it is moving with a constant speed
   2. it is falling freely towards earth
   3. its velocity keeps on increasing
   4. it is falling freely towards the earth its velocity keeps on increasing
5. a satellite is revolving round the earth in a circular orbit of radius R. work done by gravitational force in one revolution is
   1. zero
   2. $2mgR^{2}$
   3. $mgR^{2}$
   4. $mgR$
6. What is the pressure in the center of the Earth assuming the constant density.