The average resisting force that must act on a $5 \,kg$ mass to reduce its speed from $65 \,cm/s$ to $15 \,cm/s$ in $0.2 \,s$ is .......... $N$.

$A$ $10 \; N$ force is applied on a body,producing an acceleration of $1 \; m/s^2$ in it. The mass of the body is ...... $kg$.

The linear momentum $p$ of a body moving in one dimension varies with time according to the equation $p = a + bt^2$,where $a$ and $b$ are positive constants. The net force acting on the body is

$A$ cricketer catches a ball of mass $150\; g$ in $0.1\; s$ moving with a speed of $20\; m/s$. The force experienced by the cricketer is ..... $N$.

When will a body of mass $20 \ kg$ moving at $15 \ m s^{-1}$,subjected to a retarding force of $100 \ N$,come to rest (in $s$)?

The driver of a three-wheeler moving with a speed of $36\; km/h$ sees a child standing in the middle of the road and brings his vehicle to rest in $4.0\; s$ just in time to save the child. What is the average retarding force (in $N$) on the vehicle? The mass of the three-wheeler is $400\; kg$ and the mass of the driver is $65\; kg$.