Home
Class 11
PHYSICS
If a gymnast sitting on a rotating stool...

If a gymnast sitting on a rotating stool, with his arms out stretched, suddenly lowers his hands, what will happen?

A

the angular velocity decreases

B

his moment of inertia decreases

C

the angular velocity stays constant

D

the angular momentum increases

Text Solution

Verified by Experts

The correct Answer is:
B
When hands are lowered R decrease. Moment of inertia I will be decreased.
Sicne `I=MR^(2)`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • MOTION OF SYSTEM OF PARTICLES AND BODIES

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTIONS & ANSWER (VERY SHORT ANSWER QUESTIONS)|24 Videos

  • MOTION OF SYSTEM OF PARTICLES AND BODIES

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTIONS & ANSWER (SHORT ANSWER QUESTIONS)|38 Videos

  • MOTION OF SYSTEM OF PARTICLES AND BODIES

    PREMIERS PUBLISHERS|Exercise TEXTBOOK QUESTIONS & ANSWERS (NUMERICAL PROBLEMS)|12 Videos

  • LAW OF MOTION

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTIONS & ANSWERS (VI Numerical Problems)|62 Videos

  • NATURE OF PHYSICAL WORLD AND MEASUREMENT

    PREMIERS PUBLISHERS|Exercise OTHER IMPORTANT QUESTIONS & ANSWERS (III. Short Answer Questions.)|24 Videos

Similar Questions

Explore conceptually related problems

A man is sitting on a rotating stool with his arms outstretched. If suddenly he folds his arms the angular velocity of the man would

A child stands at the centre of turn table with his two arms out stretched. The turn table is set rotating with an angular speed of 40 rpm. How much is the angular speed of the child if he folds his hands back and thereby reduces his moment of inertia to 2/5 times the initial value? Assume that the turn table rotates without friction (ii) Show that the child's new kinetic energy of rotation is more than the initial kinetic energy of rotation. How do you account for this increase in kinetic energy?

Knowledge Check

  • If a person standing on a rotating disc stretches out his hands, the angular speed will

    A
    increases
    B
    decreases
    C
    remain same
    D
    none of these

  • If a person standing on a rotatig disc stretches out his hands the angular speed will

    A
    increase
    B
    decrease
    C
    remain same
    D
    None

    • Similar Questions

    Explore conceptually related problems

    While catching a cricket ball the fielder lowers his hands backwards . Why ?

    While catching a cricket ball the fielder lowers his hands backwards. Why ?

    While catching a cricket ball the fielder lowers his hands backwards. Why ?

    While catching a cricket ball the fielder lowers his hands backwards. Why?

    What did Van Helmont find out with his experiment?

    Jagaseesh was rotating a stone tied to an elastic rubber band. As time passes he kept on increasing its speed of rotation. As the speed increased, the length (i.e. radius) of the band was also increasing. His father Mr. Sridhar watched this and called Jagadeesh. When Jagadeesh came near by his father rotating the stone tied to the elastic band, he asked how this happened? (ii) What are Apogee and Perigee?

    Home
    Profile