alleryA pendulum of mass m swings to amplitude angle θ. At the lowest point of swing, the TENSION in the string equals:
Amg
Bmg(2 − cos θ)
Cmg(3 − 2cos θ)
D2mg sin θ
Answer & Solution
Correct answer: C. mg(3 − 2cos θ)
**At the lowest point:** T − mg = mv²/L (centripetal).
v² at bottom = 2gL(1 − cos θ) (energy conservation from amplitude).
We have So T = mg + 2mg(1 − cos θ).
So So T = mg(3 − 2cos θ).
For θ = 60°: T = mg(3 − 1) = 2mg.
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