Question 535078
The kinetic energy of a moving body is directly proportional to its mass and the square of its speed.
e = k*m*s^3
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If the mass of a bullet is halved, by what factor must its speed be increased to have the same kinetic energy as before?
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Multiply and divide the right side by 1/2:

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e = k(1/2)m *(s^2/(1/2)
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e = k(m*s^2/(1/2))
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e = k(m*2s^2
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e = k(m*(sqrt(2)s)^2
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Ans: Multiply speed by sqrt(2)
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Cheers,
Stan H.
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