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Class 11PhysicsSystem of Particles and Rotational MotionConservation of angular momentum (combined translation and rotational motion)
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$A$ small object is attached to a light string which passes through a hollow tube. The tube is held by one hand and the string by the other. The object is set into rotation in a circle of radius $r_1$. The string is then pulled down,shortening the radius of the circle to $r_2$. The ratio of the new kinetic energy to the original kinetic energy is

  • A
    $\frac{r_1}{r_2}$
  • B
    $1$
  • C
    $\left(\frac{r_1}{r_2}\right)^2$
  • D
    $\left(\frac{r_2}{r_1}\right)^2$
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Class 11 Questions

Class 11

Physics Questions

Chapter

System of Particles and Rotational Motion

Subtopic

Conservation of angular momentum (combined translation and rotational motion)

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