Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • Medical
  • A variable torque  is applied to a rigid body which varies with angular displacement&nb

A variable torque \small '\tau' is applied to a rigid body which varies with angular displacement  \small '\theta ' as-

\small \tau=\sin \theta+\cos \theta

Find the rotational kinetic energy of the rigid body at \small \theta=2 \pi\ \mathrm{rad}, if initially it  was at rest.

Option: 1

0 Joule


Option: 2

2 Joule


Option: 3

1 Joule


Option: 4

3 Joule


Answers (1)

best_answer

\begin{aligned} & W=\int(\tau)(d \theta) \\ & W=\int_0^{2 \pi}(\sin \theta+\cos \theta) d \theta \\ & W=\int_0^{2 \pi} \sin \theta d \theta+\int_0^{2 \pi} \cos \theta d \theta \\ & W=-[\cos \theta]_0^{2 \pi}+[\sin \theta]_0^{2 \pi} \\ & W=-[\cos 2 \pi-\cos 0]+0=0 \end{aligned}

From Work-Energy Theorem, 

\begin{aligned} & W=\Delta K \\ & \Delta K=0 \\ & K_f-K_i=0 \\ & K_f=0 \end{aligned}
 

Posted by

Divya Prakash Singh

View full answer

NEET 2024 Most scoring concepts

    Just Study 32% of the NEET syllabus and Score up to 100% marks

Similar Questions

Trending Articles/News

anam-khan

Karnataka: NEET candidate dies by suicide; no note recovered
anam-khan

CBSE Re-evaluation Row: Dharmendra Pradhan seeks detailed report on technical failures
anam-khan

Before NEET, CMC Vellore’s unique MBBS admissions tested aptitude along with merit; paper-leak restarts debate

Latest Question