Question

A particle of mass 1 $kg$ slides down a frictionless track (AOC) starting from rest at a point A (height 2 $m$). After reaching C, the particle continues to move freely in air as a projectile. When it reaches its highest point P(height 1 $m$) the kinetic energy of the particle (in $J$) is:(Figure drawn is schematic and not to scale; take $g=10m/s^2$)

Answer 1

As the particle starts from rest the total energy at point $A=mgh=T.E_A$( where $h=2m$)
After reaching point P
$$\begin{array}{cc}& T.E_c=K.E.+mgh\\ & \text{By conservation of energy}\\ & T.E_A=T.E_p\\ & ⟹K.E.=mgh=10J\end{array}$$