Given that $W = \vec F \cdot \vec s = 0$ and $F \neq 0, s \neq 0$,then

The kinetic energy $(KE)$ acquired by a mass $m$ in travelling a certain distance $d$,starting from rest,under the action of a constant force $F$ is ..........

If a person is pushing a box inside a moving train,the work done in the frame of the earth will be: (where $\vec{s}$ is the displacement of the box in the train and $\vec{s}_0$ is the displacement of the train relative to the ground)

$A$ force of $5 \ N$ acts on a stationary body of mass $15 \ kg$. What is the work done during the first second of motion?

$A$ force of $5 \ N$ is required to maintain a constant velocity of $2 \ m/s$ for a block of mass $10 \ kg$ on a rough surface. The work done by this force in $1 \ minute$ is: (in $J$)

$A$ ball of mass $m$ is attached to a string whose other end is fixed. The system is free to rotate in a vertical plane. When the ball swings,no work is done on the ball by the tension in the string. Which of the following statements is the correct explanation?