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Karnataka Board PUCPUC Science Class 11

The bob A of a pendulum released from 30° to the vertical hits another bob B of the same mass at rest on a table, as shown in the figure. How high does the bob A rise - Physics

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Question

The bob A of a pendulum released from 30° to the vertical hits another bob B of the same mass at rest on a table, as shown in the figure. How high does the bob A rise after the collision? Neglect the size of the bobs and assume the collision to be elastic.

Answer in Brief
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Solution

When the bob A of a pendulum, released from an angle of 30° to the vertical, collides with another stationary bob B of the the same mass, the collision being elastic, their velocities are exchanged. As a result of this elastic collision, bob A will come to rest immediately after the impact, while bob B will acquire the velocity that bob A had just before the collision. Therefore, after the collision, bob A does not rise again; it remains at rest

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Chapter 5: Work, Energy and Power - EXERCISES [Page 91]

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NCERT Physics [English] Class 11
Chapter 5 Work, Energy and Power
EXERCISES | Q 5.17 | Page 91

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