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    I'd be grateful if someone could help me with this question. I thought you would use F=ma, but i'm wrong. Thanks

    A lift and its passengers with a total mass of 500kg accelerates upwards at 2ms^-2. Assume that g=10ms^-2. What is the tension in the cable holding the lift?

    Thanks.
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    Sorry you've not had any responses about this. Are you sure you've posted in the right place? Here's a link to our subject forum which should help get you more responses if you post there.

    You can also find the Exam Thread list for A-levels here and GCSE here. :dumbells:


    Just quoting in Puddles the Monkey so she can move the thread if needed
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    (Original post by liamsullivan)
    I'd be grateful if someone could help me with this question. I thought you would use F=ma, but i'm wrong. Thanks

    A lift and its passengers with a total mass of 500kg accelerates upwards at 2ms^-2. Assume that g=10ms^-2. What is the tension in the cable holding the lift?

    Thanks.
    Well F=ma is useful here, but you've got to remember that the tension in the cable isn't zero when the lift is stationary.
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    (Original post by liamsullivan)
    I'd be grateful if someone could help me with this question. I thought you would use F=ma, but i'm wrong. Thanks

    A lift and its passengers with a total mass of 500kg accelerates upwards at 2ms^-2. Assume that g=10ms^-2. What is the tension in the cable holding the lift?

    Thanks.
    You need to consider the forces acting on the elevator to provide for this accelration. F=ma is what you use but F is a number of different forces (making up the net force) acting on the elevator not just one. There is a tension upwards and the weight of the passengers + lift downwards. Since accerlation upwards then the tension must be greater as tension is up and weight force is down. So:

    T - mg = ma
    T - 500g = (500x2)
    T = 5900N
 
 
 
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