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Gigi asked in Science & MathematicsPhysics · 1 month ago

I don’t understand these problems, please help?


9) A 1200 kg car moves around a turn of radius, R = 50.0 m. Determine the acceleration of the car and the FNet that must be delivered by the roadway is the car takes the turn (A) at a velocity of 15.0 m/s, or (B) a velocity of 30.0 m/s. Comment on the differences when the velocity is doubled.

Update 2:


A) Do a force diagram of the cup/water when it is upside down at the top of the circle. (B) Write a force statement, given your force diagram. (C) Given your force diagram and force statement, explain why the water/cup stay on the board. (D) Determine, in terms of R and g, the critical velocity at which the cup/water would fall from the board. HINT: Let FN  0 in your force statement and solve.

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1 Answer

  • NCS
    Lv 7
    1 month ago
    Favorite Answer

    This is far too small to read. But I get the impression in #9 that they want the friction force (centripetal force) and have provided the mass, radius and velocity. Then

    F = mv²/r.

    #10 looks like the old "water in the upside-down glass" trick. For the water to not spill out, you need the centripetal acceleration to be at least as great as gravity:

    v² / r ≥ g

    meaning at the threshold, v = √(g*r)

    If you need more help than I've given, use Update to type in your question and any necessary supporting data. Hope this helps!

    Source(s): Please revisit this working: and post better images!
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