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QJEEM23Ph5a9d: JEE Main 2023 Physics - Class 11 JEEM23Ph5a9d Solution: The momentum of a body is increased by . The percentage…

The momentum of a body is increased by 50%50 \% . The percentage increase in the kinetic energy of the body is ___________ %\% .

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The momentum (p) and kinetic energy (K) of a body are related by the equations:

p=mvp = mv ,

K=12mv2K = \frac{1}{2}mv^2 ,

where m is the mass and v is the velocity of the body.

We can express v in terms of p and m:

v=pmv = \frac{p}{m} ,

and substitute this into the equation for K to get:

K=p22mK = \frac{p^2}{2m} .

So, the kinetic energy is proportional to the square of the momentum.

If the momentum is increased by 50%, the new momentum is 1.5p, and the new kinetic energy is:

K′=(1.5p)22m=2.25p22m=2.25KK' = \frac{(1.5p)^2}{2m} = \frac{2.25p^2}{2m} = 2.25K .

The percentage increase in the kinetic energy is then:

K′−KK×100=2.25K−KK×100=1.25×100=125%\frac{K'-K}{K} \times 100 = \frac{2.25K - K}{K} \times 100 = 1.25 \times 100 = 125\% .

So, the percentage increase in the kinetic energy of the body is 125%.

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