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Question on kinetic energy down an inclined slope Watch

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    Hello everyone!
    I have been trying to solve this problem for quite some time but with little success. I cannot even seem to find the correct answer and my Mid-Terms are coming up. I figured you guys can help me out with this:

    http://physics.dalzielhigh.org.uk/Ph...20question.pdf

    Basically, I am unable to solve part c) but the rest is pretty simple. I would really appreciate a solution and explanation to this question.
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    So u have the acceleration, the initial velocity and the displacement. U can use a suvat equation to find the final speed, then u can sub this into ur kinetic energy formula

    Hope i helped bro👊🏾
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    (Original post by Shaanv)
    So u have the acceleration, the initial velocity and the displacement. U can use a suvat equation to find the final speed, then u can sub this into ur kinetic energy formula

    Hope i helped bro👊🏾
    Ah! I see, that makes perfect sense. Can't believe I ignored those formulas. Really appreciate the quick help, mate. And you definitely helped
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    (Original post by UsedCarSalesman)
    Ah! I see, that makes perfect sense. Can't believe I ignored those formulas. Really appreciate the quick help, mate. And you definitely helped
    Glad to hear it good luck in ur mid terms
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    the KE at A is increased by the loss of GPE at B, but it is also decreased by the work against the frictional force.

    KE at A = .5x2600x52 J

    GPE loss = 2600x 9.8x 75xsin12

    work done = 75 x 1400
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    (Original post by Shaanv)
    Glad to hear it good luck in ur mid terms
    Thanks man! My first exam and hopefully it goes well. Quick question, a = 1.5 m/s^2 right? Because I feel like the acceleration changes so it won't be that.
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    (Original post by UsedCarSalesman)
    Thanks man! My first exam and hopefully it goes well. Quick question, a = 1.5 m/s^2 right? Because I feel like the acceleration changes so it won't be that.
    The acceleration will be the value u have calculated as the forces remain constant, i havent done the math but ur answer to part b will be the constant acceleration of the van.

    The bear working out also works, but if u have never encountered conservation of energy in that form before, then this method is not for u
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    (Original post by the bear)
    the KE at A is increased by the loss of GPE at B, but it is also decreased by the work against the frictional force.

    KE at A = .5x2600x5 J

    GPE loss = 2600x 9.8x 75xsin12

    work done = 75 x 1400
    While I understand what you are stating, I am unable to follow up on getting the final answer. Apologies for I am unfamiliar with their relation to work done. What do you suggest is the final answer?
    Anyways, I really appreciate the help!
    The other method seemed easier but I feel like I should use two to confirm my answer.
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    i get 325225 J
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    The working out for the bear method

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