Question

If the displacement $x$ of a particle of mass $m$ is directly proportional to time, net force acting on it is _____________.

Answer 1

$x=ktv=\frac{dx}{dt}=ka=\frac{dv}{dt}=0$

So, the net force on the particle $=F=ma=m\cdot 0=0$

So, the net force on the particle is zero.