99 Percentile Qs Bank for JEE MainPhysicsMechanical Properties of Solids
The potential energy U between two molecules as a function of the distance X between them has been shown in the figure. The two molecules are
Options
- ARepelled when x lies between A and B and are repelled when x lies between B and C .
- BAttracted when x lies between B and C and are repelled when x lies between A and B .
- CAttracted when they reach B .
- DRepelled when they reach B .
Correct answer
B. Attracted when x lies between B and C and are repelled when x lies between A and B .
Step-by-step solution
Force in terms of variation of potential energy is given by F=- d U d x . d U d x in potential energy-displacement curve is slope of the curve. In AB region slope is negative, hence force will be positive which means repulsive force in nature. In BC region slope is positive, hence force will be negative which means attractive force in nature.