From the law of conservation of angular momentum So, mvry′k2k1k2k1k2k1k1k2=mv′2r=2y=21mv221mv2=v′2y2=(2v)2y2=41=41k2=4k1
NEET UG 2011 — Physics Mechanics
2011mcqmedium
A small mass attached to a string rotates on frictionless table top as shown. If the tension is the string is increased by pulling the string causing the radius of the circular motion to decrease by a factor of 2 , the kinetic energy of the mass will 
Official previous-year question
Held on 30 Apr 2011 · Verified 9 Jul 2026.
Options
- A
remain constant
- B
increase by a factor of 2
- C
increase by a factor of 4
- D
decrease by a factor of 2
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