Two constant forces ${F_1} = 2\hat i - 3\hat j + 3\hat k$ $(N)$ and ${F_2} = \hat i + \hat j - 2\hat k$ $(N)$ act on a body and displace it from the position ${r_1} = \hat i + 2\hat j - 2\hat k$ $(m)$ to the position ${r_2} = 7\hat i + 10\hat j + 5\hat k$ $(m)$. What is the work done in $J$?

$A$ string is used to pull a block of mass $m$ vertically up by a distance $h$ at a constant acceleration $\frac{g}{4}$. The work done by the tension in the string is ...............

$A$ body,constrained to move in the $Y$-direction,is subjected to a force given by $\vec{F} = (-2\hat{i} + 15\hat{j} + 6\hat{k})\,N$. What is the work done by this force in moving the body a distance $10\,m$ along the $Y$-axis?

$A$ force $\vec{F} = 2\hat{i} + b\hat{j} + \hat{k}$ is applied on a particle and it undergoes a displacement $\vec{S} = \hat{i} - 2\hat{j} - \hat{k}$. What will be the value of $b$,if the work done on the particle is zero?

Work done in raising a box depends on

An adult weighing $600 \, N$ raises the centre of gravity of his body by $0.25 \, m$ while taking each step of $1 \, m$ length in jogging. If he jogs for $6 \, km$,calculate the energy utilised by him in jogging assuming that there is no energy loss due to friction of ground and air. Assuming that the body of the adult is capable of converting $10 \, \%$ of energy intake in the form of food,calculate the energy equivalents of food that would be required to compensate for the energy utilised for jogging.