Question 2

A uniform bar of mass M is supported by a pivot at its top, about which the bar can swing like a pendulum. If a force, F, is applied perpendicularly to the lower end of the bar as in the diagram, how big must F be in order to hold the bar in equilibrium at an angle θ from the vertical?

• A.     One can't tell without knowing the length of the bar.
• B.     2Mg
• C.     Mg/2
• D.     2Mg sin θ
• E.     Mg sin θ
• F.     (Mg/2) sin θ
• G.     2Mg cos θ
• H.     Mg cos θ
• I.     (Mg/2) cos θ
• J.     None of the above

Question 1

Question 3

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