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Mechanics

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    Calculate the force required (in Newtons) to accelerate a train of mass 500 tonnes from rest to a velocity of 30km/hr in 20 minutes.Give your answer to the nearest whole number.

    Need help please...
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    You need to show your attempt at the working first. This isn't a homework service.

    This is a daft model without any resistance forces but you just need to combine v=u+at with F=ma.
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    (Original post by Sarmi)
    Calculate the force required (in Newtons) to accelerate a train of mass 500 tonnes from rest to a velocity of 30km/hr in 20 minutes.Give your answer to the nearest whole number.

    Need help please...
    Firstly, I like to work in standard units, so I will convert

    30kph = 8 1/3 m/s
    20 minutes = 1200s
    500 tonnes=500000kg

    So, we know a=(v-u)/t. So a=(8 1/3 - 0)/1200. a=0.00694444... m/s^2

    We know f = m a

    F = 500000 x 0.00694444...
    F = 3,472.2222 N
    F = 3,472 N
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    S
    U= 0
    V= 30,000
    A=?
    T= 20*60

    Sub into v=u + at
    Then sub a into F=(mass of truck in kg) * accelearation
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    Thank You
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    (Original post by CharlieBoardman)
    Firstly, I like to work in standard units, so I will convert

    30kph = 8 1/3 m/s
    20 minutes = 1200s
    500 tonnes=500000kg

    So, we know a=(v-u)/t. So a=(8 1/3 - 0)/1200. a=0.00694444... m/s^2

    We know f = m a

    F = 500000 x 0.00694444...
    F = 3,472.2222 N
    F = 3,472 N
    You're not supposed to post full solutions mate...

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