• # question_answer A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to         [AIEEE 2004] A)             ${{x}^{2}}$ B)               ${{e}^{x}}$ C)             x          D)             ${{\log }_{e}}x$

This condition is applicable for simple harmonic motion. As particle moves from mean position to extreme position its potential energy increases according to expression $U=\frac{1}{2}k{{x}^{2}}$ and accordingly kinetic energy decreases.