Find the mass of the rocket as a function of time, if it moves with a constant acceleration `a`, in absence of external forces. The gas escapes with a constant velocity `u` relative to the rocket and its mass initially was `m_0`.

Find the law according to which the mass of the rocket varies with time, when the rocket moves with a constant acceleration w, the external forces are absent, the gas escapes with a constant velocity u relative to the rocket, and its mass at the initial moment equals m_0 .

Show that in the absence of any external force, the velocity of the centre of mass remains constant.

If M is mass of rocket, r is rate of ejection of gases and u is velocity of gases with respect to rocket then acceleration of the rocket dv/dt is equal to

Average velocity of a particle moving in a straight line, with constant acceleration a and initial velocity u in first t seconds is.

A particle moves in a straight line with constant acceleration If it covers 10 m in first second and 20 m in next second find its initial velocity.

A rocket moves in the absence of external forces by ejecting a steady jet with velocity u constant relative to the rocket. Find the velocity v of the rocket at the moment when its mass is equal to m, if at the initial moment it possessed the mass m_0 and its velocity was equal to zero. Make use of the formula given in the foregoing problem.

A particle moves rectilinearly with initial velocity u and constant acceleration a. Find the average velocity of the particle in a time interval from t=0 to t=t second of its motion.

A block of mass m is kept on an inclined plane of a lift moving down with acceleration of 2m//s^(2) . What should be the coefficient of friction for the block to move down with constant velocity relative relative to lift?