Question

The figure shows the potential energy function $U(x)$ of a system in which a particle is in one-dimensional motion. Arrange regions $AB$ , $BC$ , $CD$ and $DE$ according to the magnitude of thefore on tho particle in decreasing order

• A. $BC$ , $DE$ , $AB$ , $CD$
• B. $BC$ , $AB$ , $CD$ , $DE$
• C. $AB$ , $CD$ , $BC$ , $DE$
• D. $CD$ , $AB$ , $DE$ , $BC$

Answer 1

Answer: (A)

Relation between force and potential energy is given by
$F\left(X\right) = \frac{-dU\left(X\right)}{dx} = -$ (slope of graph)
From graph,
In case of $(i), \frac{dU}{dx}$ is maximum
$\Rightarrow - \frac{dU}{dx}$ is minimum
In $BC, \frac{dU}{dx} = 0$
$\Rightarrow F = 0$
If we compare $- (\frac{dU}{dx})$ of $DE$ $AB$ then magnitude of force of $DE$ is greater then $B$.