A pendulum of length 0.80m and mass 0.25kg is released from rest at an initial angular displacement of 4.0∘.
Assume any approximations necessary for small-amplitude motion are acceptable.
(a) Convert the initial angular displacement to radians and justify whether it meets the criterion for the small-angle approximation.
(b) Calculate the magnitude of the restoring torque acting on the bob at the instant it is released.
(c) Determine the maximum tangential acceleration of the bob during its motion.
(d) Using the small-angle model, calculate the time required for the bob to travel from one extreme of its motion to the other for the first time after release.