A rocket of maxx `3xx10^6`kg takes off from a launching pad and acquires a verticle velcoity of 1km//s and an altitude of 25km. Calculate its (a) potential energy (b) kineitc energy.

A geostationary satellite orbits the Earth at a height of nearly 36,000 km from the surface of earth. What is the potential due to earth's gravity at the site of tthis satllite ? (Take the potential energy at infinity to be zero). Mass of the Earth = 6.0 xx 10^(24) kg , radius = 6400 km, G = 6.67 xx 10^(-11) Nm^(2)//kg^(2) .

A rocket consumes 24kg of fuel per second The burnt gases escape the rocket at a speed of 6.4km//s relative to the rocket Calculate the upthrust recevied by the rocket Also calculate the velocity acquired by the rocket when the mass redues to 1//100th of its initial mass.

(a) A rocket set for vertical firing weighs 50kg and contains 450kg of fuel. It can have a maximum exhaust velocity of 2km//s . What should be its minimum rate of fuel consumption (i) to just lift off the launching pad? (ii) to give it an initial acceleration of 20m//s^2 ? (b) What will be the speed of the rocket when the rate of consumption of fuel is 10kg//s after whole of the fuel is consumed? (Take g=9.8m//s^2 )

A bomb of mass 40 kg is dropped from an aeroplane at a height of 1 km above the ground. What is its kinetic energy (i) at the end of 10 s and (ii) on reaching the ground ?

A body of mass 10 kg is dropped from a height of 20 m. (Take g = 10 m/s^2) Fuid its potential energy before it is dropped

Two earth satellites A and B , each of mass m are to be launched into circular orbits about earth's centre at altitudes 6400 km and 19200 km , respectively. The radius of earth is 6400 km . Find (i) the ratio of potential energy of B to that of A , (ii) ratio of kinetic energy of B to that of A and (iii) which one has greater total energy?