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Net Forces Question

  1. Mar 16, 2008 #1
    A toy car of mass 50g travels down a smooth incline at 30 degrees to the horizontal. Friction can be ignored.

    Also Gravity is assumed to be 10ms

    Calculate the net force on the car as it rolls down the slope:

    For this I use M x G sin 30

    so .05 x 10 sin 30 and got .25N - Hopefully this is right

    The second part of this question is - Calculate the forces of the incline on the car as it travels down the slope.

    I do not really understand what is being asked here - The only thing I can think it to be is Fn which would be .5N

    Any help you could give me would be great.
  2. jcsd
  3. Mar 16, 2008 #2
    It's indeed Fn what is asked, but Fn is not .5 N on an incline.

    De force of gravity and the normal force must add to give the net force.
  4. Mar 16, 2008 #3
    It asks you the forces arising on the car due to the incline my friend.

    My questions to you are:

    What is frictional force? Is it a property of the body?
    What is your take on Normal Force? What is its origin?
    Is gravity arising due to the incline?
    Is there any other force acting on the incline?

    Answer these questions to your knowledge and the second part becomes a piece of meat.

    ©ALwAyS gAmE ž
  5. Mar 16, 2008 #4

    Doc Al

    User Avatar

    Staff: Mentor

    You mean 10 m/s^2


    To find the normal force, analyze force components perpendicular to the incline. (The net force in that direction must be zero.)
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