JEE Main & Advanced Sample Paper JEE Main Sample Paper-26

  • question_answer
    When a ceiling fan is switched off, its angular velocity falls to half while it makes 36 rotations. how many rotation will it make before coming to rest?

    A)  24                               

    B)  36

    C)  18                               

    D)  12

    Correct Answer: D

    Solution :

    Angular motion \[={{\omega }^{2}}=\omega _{0}^{2}-2\alpha \theta \] (here, (\[\omega =0\]) \[\therefore \,\,0=\,{{\left( \frac{{{\omega }_{0}}}{2} \right)}^{2}}-2\times \,\frac{\omega _{0}^{2}.\,\theta }{16\times 12\pi }\] Or \[\theta =24\,\pi \,or\,\,\theta =12\times 2\pi \] But \[2\pi =1\] cycle, So, \[\theta =12\] cycle 

You need to login to perform this action.
You will be redirected in 3 sec spinner