A heavy body of mass $25\, kg$ is to be dragged along a horizontal plane $\left( {\mu = \frac{1}{{\sqrt 3 }}} \right).$ The least force required is ........ $kgf$
$25$
$2.5$
$12.5$
$6.25$
Which of the following statements is not true
A block of mass $70\,kg$ is kept on a rough horizontal surface $(\mu = 0.4)$. A person is trying to pull the block by applying a horizontal force, but the block is not moving. The net contact force exerted by the surface on the block is $F$, then
A particle of mass $m$ is at rest at the origin at time $t = 0$. It is subjected to a force $F(t) = F_0e^{-bt}$ in the $x$ -direction. Its speed $v(t)$ is depicted by which of the following curves ?
Pulling force making an angle $\theta $ to the horizontal is applied on a block of weight $W$ placed on a horizontal table. If the angle of friction is $\alpha $, then the magnitude of force required to move the body is equal to
Two blocks $A$ and $B$ are released from the top of a rough inclined plane so that $A$ slides along the plane and $B$ falls down freely. Which will have higher velocity on reaching the ground ?