## Textbooks & Solution Manuals

Find the Source, Textbook, Solution Manual that you are looking for in 1 click.

## Tip our Team

Our Website is free to use.
To help us grow, you can support our team with a Small Tip.

## Holooly Tables

All the data tables that you may search for.

## Holooly Help Desk

Need Help? We got you covered.

## Holooly Arabia

For Arabic Users, find a teacher/tutor in your City or country in the Middle East.

Products

## Textbooks & Solution Manuals

Find the Source, Textbook, Solution Manual that you are looking for in 1 click.

## Holooly Arabia

For Arabic Users, find a teacher/tutor in your City or country in the Middle East.

## Holooly Help Desk

Need Help? We got you covered.

## Q. 20.2

A wooden top has a moment of inertia of $2.4 × 10^{-5}$ kg $m^{2}$ about its axis. It starts spinning when a string wound round the spindle of the top is pulled with a constant force of 0.5 N. Assuming there is no loss of energy due to friction, find the angular speed attained by the top when the length of the string is 0.3 m.

## Verified Solution

The work done in pulling the string is 0.5 × 0.3 = 0.15 J and, as no energy is lost in the process, this is equal to the gain in kinetic energy of the top. So the angular speed attained is ω rad $s^{-1}$, where

$\frac{1}{2} × 2.4 × 10^{-5}$ ω² = 0.15

⇒           ω² = 12 500.

The angular speed is 112 rad $s^{-1}$ correct to 3 significant figures.