Question

If the momentum of a body is increased by 100 %, then the percentage increase in the kinetic energy is

• A. 150 %
• B. 200 %
• C. 225 %
• D. 300 %

Answer 1

Answer: (D)

300 %

Answer 2

$E = \frac { P ^ { 2 } } { 2 m }$ ⇒ $\frac { E _ { 2 } } { E _ { 1 } } = \left( \frac { P _ { 2 } } { P _ { 1 } } \right) ^ { 2 } = \left( \frac { 2 P } { P } \right) ^ { 2 } = 4$

$E _ { 2 } = 4 E _ { 1 }$ $= E _ { 1 } + 3 E _ { 1 } = E _ { 1 } + 300$% of $E _ { 1 }$.