$A$ man starts walking from a point on the surface of the Earth (assumed smooth) and reaches the diagonally opposite point. What is the work done by him?

At time $t=0$,a particle starts moving along the $x$-axis. If its kinetic energy increases uniformly with time $t$,the net force acting on it must be proportional to

Force acting on a particle moving in a straight line varies with the velocity of the particle as $F = \frac{K}{v}$,where $K$ is a constant. The work done by this force in time $t$ is

$A$ body is being raised to height $h$ from the surface of the Earth. What is the sign of work done by $(a)$ applied force and $(b)$ gravitational force?

If work is done by a body against a force,is the work considered positive or negative?

$A$ force $\overrightarrow{F} = 6\hat{i} + 2\hat{j} - 3\hat{k}$ acts on a particle and produces a displacement of $\overrightarrow{s} = 2\hat{i} - 3\hat{j} + x\hat{k}$. If the work done is zero,the value of $x$ is