Physics · JEE | WORK, ENERGY AND POWER

Based on the parabolic plots of potential energy \( V \) and kinetic energy \( K \) of a block attached to a spring obeying Hooke's law (shown in the chapter), what happens to the total mechanical energy \( E = K + V \) as the block oscillates between \( -x_m \) and \( +x_m \)?

1. A
   It continuously increases from \( -x_m \) to \( +x_m \).
2. B
   It remains constant at all points.
3. C
   It is zero at the equilibrium position \( x = 0 \).
4. D
   It equals kinetic energy only at the turning points.