$A$ block of mass $M$ is pulled a distance $x$ on a horizontal table. The work done by the weight (gravitational force) is:

$A$ force $\vec F = 2\hat i - 3\hat j + 7\hat k \text{ (N)}$ acts on a particle which undergoes a displacement of $\vec S = 7\hat i + 3\hat j - 2\hat k \text{ (m)}$. Calculate the work done by the force in $J$.

$A$ simple pendulum bob of mass $m$ is raised to a maximum height $h$. Find the work done by the gravitational force as the pendulum moves from one extreme end to the other.

$A$ 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

$A$ chain of mass $M$ and length $L$ is hanging from the edge of a table such that one-third of its length is hanging off the edge. The work done to pull the hanging part onto the table is:

Show that a force that does no work must be a velocity-dependent force.