Question

A body is projected with kinetic energy E such that its range is maximum.Its potential energy at the maximum height is

• A. 4 K
• B. 3 K
• C. 2 K
• D. Zero

Answer 1

The correct option is C 2 K

K.E = E = $\frac{1}{2}m{u}^2$; [$\because \theta ={45}^0$]
P.E = mgh = $mg\left(\frac{u^{2}si{n}^2\theta }{2g}\right)$
P.E = $\left(\frac{1}{2}m{u}^2\right)si{n}^{2}45=E[\frac{1}{\sqrt{2}}{]}^2$
P.E = $\frac{E}{2}$