$A$ body of mass $2 \, kg$ is projected vertically upwards with a velocity of $2 \, m/s$. The kinetic energy $(K.E.)$ of the body just before striking the ground is ............. $J$.

Explain the conservation of mechanical energy using the example of a falling ball.

$A$ body of mass $2 \, kg$ slides down a curved track which is a quadrant of a circle of radius $1 \, m$ as shown in the figure. All the surfaces are frictionless. If the body starts from rest,its speed at the bottom of the track is ............. $m/s$.

The figure shows the vertical section of a frictionless surface. $A$ block of mass $2\, kg$ is released from position $A$. Its kinetic energy $(KE)$ as it reaches position $C$ is .............. $J$.

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:

$A$ toy gun fires a plastic pellet with a mass of $0.5\ g$. The pellet is propelled by a spring with a spring constant of $1.25\ N/cm$, which is compressed $2.0\ cm$ before firing. The plastic pellet travels horizontally $10\ cm$ down the barrel (from its compressed position) with a constant friction force of $0.0475\ N$. What is the speed (in $SI\ units$) of the bullet as it emerges from the barrel?