$A$ 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

$A$ block of mass $2 \,kg$ is pulled at a constant speed with a taut rope along a frictionless plane that is inclined at $30^{\circ}$. Then the work done by the tension in the rope in pulling it a distance $4 \,m$ along the inclined plane in joule is (acceleration due to gravity $= 10 \,ms^{-2}$)

$A$ force of $(5\hat i + 6\hat j - 7\hat k) \, N$ is applied to a body of mass $10 \, kg$,causing it to displace from position $(4\hat i - 2\hat j + 5\hat k) \, m$ to $(8\hat i + 6\hat j - 3\hat k) \, m$. Calculate the work done in $J$.

$A$ weightlifter lifts a weight off the ground and holds it up.

$A$ force of magnitude $50\, N$ acting along $\hat{i} + \hat{j} + \hat{k}$ displaces a point mass from $(5, 9, 7)$ to $(4, 8, 6)$. The work done by this force during this displacement is:

$A$ force of $(4 \hat{i}+2 \hat{j}+\hat{k}) \text{ N}$ is acting on a particle of mass $2 \text{ kg}$,displacing the particle from a position of $(2 \hat{i}+2 \hat{j}+\hat{k}) \text{ m}$ to a position of $(4 \hat{i}+3 \hat{j}+2 \hat{k}) \text{ m}$. The work done by the force on the particle in joules is: (in $\text{ J}$)