Work Energy And Power Question 306
Question: A certain system has potential energy given by the function $ U(x)=-ax^{2}+bx^{4} $ with constants, a, b > 0. Which of the following value of x is an unstable equilibrium point?
Options:
A) 0
B) $ \sqrt{a/2b} $
C) $ -\sqrt{a/2b} $
D) $ \sqrt{a/b} $
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ F=0 $ at $ x=0 $
and $ \pm \sqrt{2/2b};U(x)=0 $
at $ x=0 $ and $ U(x)<0 $ at $ \pm \sqrt{a/2b} $