Question

The potential energy of a particle of mass 5 kg moving in the x-y plane is given by $U=(-7x+24y)J;xandy$ and y being measured in m. If the particle starts from origin from rest, the magnitude of the conservative force acting on the particle is

• A. 25 units
• B. 24 units
• C. 7 units
• D. 84 units

Answer 1

The correct option is A 25 units

$\overrightarrow{F}=-[\frac{\partial U}{\partial x}\hat{i}+\frac{\partial U}{\partial y}\hat{j}]=-[-7\hat{i}+24\hat{j}].|\hat{F}|=\sqrt{7^2+{24}^2}=25units$