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NEET UG PHYSICS MCQ: WORK-ENERGY-POWER

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Analyzing +4 | -1

A bob of mass

m

, suspended by a string of length

l_1

, is given a minimum velocity required to complete a full circle in the vertical plane. At the highest point, it collides elastically with another bob of mass

m

suspended by a string of length

\mathrm{l}_2

, which is initially at rest. Both the strings are mass-less and inextensible. If the second bob, after collision acquires the minimum speed required to complete a full circle in the vertical plane, the ratio

\frac{\ell_1}{\ell_2}

is

View answer and explanation

Correct option: A

5

The correct answer is A (5). The ratio of lengths is determined by equating the velocities at the highest point and using conservation of energy after the elastic collision.

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