Question

Suppose a pendulum bob is swinging back and forth. If the highest point is 12.5 cm above the lowest point, what would be speed of the bob in m/s when it passes the lowest point (no friction or air resistance)? Think Conservation of Mechanical Energy.

Answer 1

Answer:

The speed of the bob  when it passes the lowest point  $V = 1.57 \frac{m}{s}$

Explanation:

Given data

$H = 12.5 \ cm = 0.125 \ m$

When a pendulum swinging back & forth then at highest point the velocity is zero and lowest point velocity is maximum.

Velocity at lowest point is given by  

$V = \sqrt{2 g H}$

$V = \sqrt{2 (9.81)(0.125)}$

$V = 1.57 \frac{m}{s}$

Therefore the speed of the bob  when it passes the lowest point $V = 1.57 \frac{m}{s}$