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    How should I work out this question?

    Q)
    Energy stored per unit mass (Jkg^-1)

    Modem spring steel - 130
    Tendon in leg - 2500
    Rubber cord. - 8000

    Show that a car of mass 1200kg would need steel springs of total mass approximately equal to 3kg to store energy when it encounters pot-holes of depth 3 cm
    (3 marks)

    I appreciate all solutions and suggestions a lot!
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    (Original post by Iluv2edgedsword)
    How should I work out this question?

    Q)
    Energy stored per unit mass (Jkg^-1)

    Modem spring steel - 130
    Tendon in leg - 2500
    Rubber cord. - 8000

    Show that a car of mass 1200kg would need steel springs of total mass approximately equal to 3kg to store energy when it encounters pot-holes of depth 3 cm
    (3 marks)

    I appreciate all solutions and suggestions a lot!
    Hi there, so you need to think about the change in potential energy when the car drops 3 cm
    So as you know the potential energy change will be  E=mgh = 1200\times 10 \times 0.03 = 360 J
    Thus the spring needs to absorb 360 J worth of energy.
    This is equivalent to 360/130= 2.76 kg which is about 3, I guess
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    (Original post by langlitz)
    Hi there, so you need to think about the change in potential energy when the car drops 3 cm
    So as you know the potential energy change will be  E=mgh = 1200\times 10 \times 0.03 = 360 J
    Thus the spring needs to absorb 360 J worth of energy.
    This is equivalent to 360/130= 2.76 kg which is about 3, I guess
    Grateful for thine help!
 
 
 
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