A uniform bar of mass π and length πΏ is pivoted at point π, as
shown in Figure 2 below. A point mass π is attached to the bar at a
distance π from point π.
Part I. The bar is released from rest from the position shown.
Immediately after the release:
(a) Draw the free-body-diagram showing all the forces acting on the
bar.
(b) Obtain an expression for the angular acceleration of the bar in
terms of π, π, πΏ, π, π, and π (π is the acceleration due to
gravity) in the fixed frame π΄ (in terms of πβ3 unit vector).
(c) Find the magnitude of π for which the angular acceleration
maximises. Briefly explain the reasoning for your choice
Part II. Now assume that the bar has an angular velocity ππ΅ πβ3
when passing through the position shown in Figure 2. For this
system:
(d) Does the angular acceleration of the bar change from the
expression obtained in Part I(b)? Explain why.
(e) How do the magnitudes of the reaction forces at π change
compared to Part I? You do not need to obtain expressions for the
forces; discuss whether each force is larger or smaller compared to
that of the system of Part I and explain why.
A uniform bar of mass 𝑚 and length 𝐿 is pivoted at point 𝑂, as shown in Figure 2 below. A point
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