A pendulum bob is released from rest at a height of 19.6 m above the lowest point of its swing. Ignoring air resistance and taking m/s, what is its speed at the lowest point?

Answer and explanation

Correct answer: C. 19.6 m/s

  1. Step 1: Energy conservation: , so .
  2. Step 2: m/s.
Answer
19.6 m/s.
Why not the others: 384.16 m/s: the square root is missing. 13.859 m/s: the factor 2 in is missing. 192.08 m/s: it multiplies and without using energy conservation.

Practise more Mechanics.

Free questions with an explanation for every one, and full timed EJU Japan mock tests.

A pendulum bob is released from rest… | EJU Japan Mechanics