Question

A ball is projected with kinetic energy E, at an angle of 60° to the horizontal. The kinetic energy of this hall at the highest point of its flight will become

• A. Zero
• B. $\frac E2$
• C. $\frac E4$
• D. $E$

Answer 1

Answer: (C)

$\frac E4$

Answer 2

Kinetic energy,
$KE=\frac 12mv^2=E$
At highest point,
$KE'=\frac 12mv^2 cos\ 2⁡θ$

$=\frac 12mv^2(\frac 14)$

$=\frac E4$

So, the correct option is (C): $\frac E4$