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What is the answer to this Kinectic Energy question ? Watch

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    A 100000kg train has a kinetic energy of 28000000J how fast is the train going?

    Could you write the answer and solution please?
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    Use the formula energy transferred = 1/2 x mass x velocity squared and rearrange
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    Kinetic Energy = 0.5 * mass * velocity2
    1/2mv2 = 28000000J

    1/2*100000*v2 = 28000000J

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    (Original post by Wildnatxox)
    A 100000kg train has a kinetic energy of 28000000J how fast is the train going?

    Could you write the answer and solution please?
    The answer would be 23.7 (1dp)
    Why?
    Well the formula for kinetic energy is:0.5 ×mass× velocity squared

    So to find the velocity you just rearrange the formula so it would be:

    The square root of 2× kinetic energy divided by the mass. In yout case it would be square root of 2 × 28000000 ÷100000.
    Hope it wasnt too confusing!
 
 
 
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