Work Energy And Power Question 219
Question: The work done by a force $ \vec{F}=( -6x^{3}\hat{i} )N, $ in displacing a particle from $ x=4mtox=-2 $ m is
Options:
A) $ 360J $
B) $ 240J $
C) $ -240J $
D) $ -360J $
Show Answer
Answer:
Correct Answer: A
Solution:
[a]
w=$ \int \limits x_1^{x_2}{Fdx} $
=$\int \limits _4^{-2}{-6x^{3}dx} $
$ =-6{{| \frac{x^{4}}{4} |}^{-2}}_4=\frac{-6}{4}[ {{( -2 )}^{4}}-{{( 4 )}^{2}} ]=360J. $
