Physics - W.E.P. Question with Solution | TestHub

Let the mass of the stone be $m$ and its initial velocity be $u$.

Initial kinetic energy is given by $E=\frac{1}{2}m{u}^2$.

At the highest point of the projectile motion, the vertical component of velocity becomes zero, while the horizontal component remains constant.

Velocity at the highest point is $v=u\cos \theta$.

Kinetic energy at the highest point is $E^{\prime }=\frac{1}{2}m{v}^2=\frac{1}{2}m(u\cos \theta {)}^2$.

$E^{\prime }=\left(\frac{1}{2}m{u}^2\right){\cos }^2\theta =E{\cos }^2\theta$.

Answer: $\mathrm{E}{\cos }^2\theta$