Question

A particle is released from a height H. At certain height its kinetic energy is two times its potential energy. Height and speed of particle at that instant are –

• A. , $\sqrt { \frac { 2 \mathrm { gH } } { 3 } }$
• B. $\frac { \mathrm { H } } { 3 }$ , 2$\sqrt { \frac { \mathrm { gH } } { 3 } }$
• C. ,$\sqrt { \frac { 2 \mathrm { gH } } { 3 } }$
• D. $\frac { \mathrm { H } } { 3 }$ , $\sqrt { 2 \mathrm { gH } }$

Answer 1

Answer: (B)

$\frac { \mathrm { H } } { 3 }$ , 2$\sqrt { \frac { \mathrm { gH } } { 3 } }$

Answer 2

\ K + U = mgH & K = 2U

\ 2U + U = mgH

Ž U = Ž mgh = Ž h = H/3

\ $\frac { 1 } { 2 }$ mv² = 2U = $\frac { 2 \mathrm { mgH } } { 3 }$ Ž v =