Question

A small mass of 0.2 kg is whirled round in a horizontal circle at the end of a string of length 0.5m at a constant angular speed of 4rad/. The tension (force) in the string in Newton is?

Answer 1

Given:

Mass, m=0.2 kg

Angular speed,$\omega$ =4 rad/s

Length of string ( radius of circle),r = 0.5m

Find The tension force.

Now,

In horizontal circular motion tension in the string is balanced by the outward centrifugal force.

$The\, centrifugal\, force = mrω^{\smash{2}}\\ So,\\ T= mrω^{\smash{2}}\\ T= 0.2kg\times 0.5m\times (4rad/s)^{\smash{2}}\\ T=1.6 \, N\\ Answer\\ The \,tension ,T=1.6N$