Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  JEEMAIN and AIPMT  >>  Physics  >>  Class11  >>  Work, Power and Energy
0 votes

A block of mass m is being pulled up a rough inclined by an agent delevering constant power P. The coefficient of friction between block and incline is $\mu$. The maximum speed of the block during the course of ascent is

$ a)\; \large\frac{P}{mg \sin \theta+\mu mg \cos \theta} \\ b)\; \large\frac{P}{mg \sin \theta-\mu mg \cos \theta} \\ c) \;\large\frac{2P}{mg \sin \theta-\mu mg \cos \theta} \\ d)\; \large\frac{3P}{mg \sin \theta-\mu mg \cos \theta}$
Can you answer this question?

1 Answer

0 votes
Force due to power P is
$F=\large\frac{p}{v}$$;f=\mu R$
$F-mg \sin \theta-\mu R=ma$
$\large\frac{P}{v}$$-mg \sin \theta - \mu mg \cos \theta=m \large\frac{dv}{dt}$
Velocity is maximum when $\large\frac{dv}{dt}$$=0$
$\large\frac{P}{v_{\Large max}}$$= mg \sin \theta +\mu mg \cos \theta$
$v_{max}= \large\frac{P}{mg \sin \theta+\mu mg \cos \theta}$
Hence a is the correct  answer


answered Aug 9, 2013 by meena.p
edited Feb 17, 2014 by meena.p

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App