Bullets of mass $50 \, g$ are fired from a gun of mass $10 \, kg$ with a velocity of $300 \, m/s$. If $5$ bullets are fired per second,then what force must a person apply on the gun so that it does not recoil? $(N)$

In a rocket,fuel burns at the rate of $1\; kg/s$. This fuel is ejected from the rocket with a velocity of $60\; km/s$. This exerts a force on the rocket equal to ......... $N$.

$A$ stationary rocket of initial mass $m_0$ is expelling exhaust gas at a steady speed $v_e$ with respect to itself. There is no external force on the rocket. When its mass is reduced to $\frac{m_0}{2}$,the velocity attained by the rocket will be:

$A$ rocket is fired upward from the earth's surface such that it creates an acceleration of $20\, m/s^2$. If after $5\, s$ its engine is switched off,the maximum height of the rocket from the earth's surface would be......$m$

$A$ conveyor belt is moving with a constant velocity $V$. Sand is being dropped on the belt at the rate of $M \text{ kg/s}$. The force necessary to keep the belt moving with a constant velocity $V \text{ m/s}$ will be

$A$ machine gun is mounted on a $2000 \,kg$ car on a horizontal frictionless surface. At some instant,the gun fires bullets of mass $10 \,g$ with a velocity of $500 \,m/s$ with respect to the car. The number of bullets fired per second is $10$. The average thrust on the system is ........ $N$.