Question

A block of mass $(M=1kg)$ is kept on smooth floor of a truck. One end of a spring of force constant $100N/m$ is attached to the block and other end is attached to the body of truck as shown in the figure. At $t=0$, truck begin to move with constant acceleration $2{\text{m/s}}^2$.

Answer 1

Let $x_0$ is the compression in equilibrium then
$K{x}_0=ma$
$x_0=\frac{ma}{K}=\frac{1\times 2}{100}=0.02A$
Amplitude $x_0=0.02m$
Compression is not equal to amplitude therefore (A) is wrong
The energy of oscillation is given as
$E=\frac{1}{2}k{A}^2=\frac{1}{2}\times 100\times {\left(\frac{2}{100}\right)}^2=0.02J$