Rankers Physics

Potential Energy & Equilibrium: Practice Problem & Solution

In a certain field, the potential energy is U = ax² – bx³, where a and b constants. The particle is in stable equilibrium at x equal to
zero
a/3b
2a/3b
2a/b

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Potential Energy & Equilibrium. Understanding the underlying formula is key to arriving at the correct answer below:

Potential Energy is U = ax² – bx³. For Equilibrium F = -dU/dx

⇒ dU/dx= 2ax- 3bx²=0

⇒ x = 2a/3b

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