A block is kept over a rough horizontal ground with coefficient of friction $\mu . \Lambda \mathrm{t}$ the instant shown, block is at rest. Take this moment as $t=0$ $\Lambda$ t this moment, a time dependent force given by $F=F_{0} e^{-t / \tau}$ starts acting on the block along horizontal. Here, $\tau$ and $F_{0}$ are known constants. The mass of the block is $m$.
The velocity time graph of the block will be like