If force $\vec{F}=-3 \hat{i}+\hat{j}+5 \hat{k}$ acts along $\vec{r}=7 \hat{i}+3 \hat{j}+\hat{k}$ then the torque acting at that point is

Susceptibility of a paramagnetic substance is

When an ideal gas $\left(\gamma=\frac{5}{3}\right)$ is heated under constant pressure, then what percentage of given heat energy will be utilised in doing external work?

In the given electrical network, the value of resistance ' $R$ ' when the current in the galvanometer will be zero, is