For a satellite moving in an orbit around the earth, ratio of kinetic energy to potential energy is
A ball is thrown vertically upwards with a velocity of 49 m/s. Calculate
(i) The maximum height to which it rises.
(ii) The total time it takes to return to the surface of the earth.
Six particles each of mass 'm' are placed at six verties A,B,C,D,Eand F of a regular hexagon of side 'a'. A seventh particle of mass 'M' is kept at center 'O' of the hexagon.
(a)Find net force on 'M'.
(b)Find net force on 'M' if particles at A is removed.
(c) Find net force on 'M' if particles at A and C are removed .
Amit buys few grams of gold at the poles as per the instruction of one of his friends. He hands over the same when he meets him at the equator. Will the friend agree with the weight of gold bought? If not, why? [Hint : The value of g is greater at the poles than at the equator.]
The earth and the moon are attracted to each other by gravitational force. Does the earth attract the moon with a force that is greater or smaller or the same as the force with which the moon attracts the earth? Why?
A ball thrown up vertically returns to the thrower after 6s. Find
(a) The velocity with which it was thrown up,
(b) The maximum height it reaches, and
(c) Its position after 4s.