$A$ knife of mass $m$ is at a height $x$ from a large wooden block. The knife is allowed to fall freely,strikes the block and comes to rest after penetrating distance $y$. The work done by the wooden block to stop the knife is ..............

$A$ body of mass $M$ is released from a height of $1.5 \ m$ on a curved track. It slides down and moves along a horizontal surface $PQ$ of length $15 \ m$. If the coefficient of friction between the body and the horizontal surface is $0.2$,at what distance from $P$ will the body come to rest (in $m$)?

Three particles $A, B$, and $C$ are thrown from the top of a tower with the same speed $u$. Particle $A$ is thrown upwards, $B$ is thrown downwards, and $C$ is thrown horizontally. If they hit the ground with speeds $V_A, V_B$, and $V_C$ respectively, then:

Under the action of a force, a $2 \,kg$ body moves such that its position $x$ as a function of time $t$ is given by $x = \alpha t^2 / 2$, where $x$ is in meters, $t$ is in seconds, and $\alpha = 1 \,m/s^2$. The work done by the force in the first two seconds is: (in $\,J$)

$A$ block of mass $1\,kg$ slides on a rough horizontal surface. If the speed of the block decreases from $10\,m/s$ to $8\,m/s$,the thermal energy developed in this process is .................. $J$.

The adjoining diagram shows the velocity versus time plot for a particle. The work done by the force on the particle is positive from