Q. 57

Expert-verified
Found in: Page 569

### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

Book edition 4th
Author(s) Randall D. Knight
Pages 1240 pages
ISBN 9780133942651

# In the discussion following Equation it was said that . Prove that this is so.

To prove , To balance the end and original energies, you must apply the energy conservation law.

See the step by step solution

## Step 1: Definition of  thermal energy

By virtue of its temperature, thermal energy is the internal energy existing in a system in thermodynamic equilibrium. Thermal energy is more difficult to convert to productive work than energy from systems that are not in thermodynamic equilibrium.

## Step 2: Explanation

The quantity of thermal energy that is transferred from one system to another is referred to as heat. The first system has a heating element.

---------(1)

The second system has a heat

--------(2)

If we have two systems, each one starts with thermal energy at a different temperature. When the two systems are coupled, they interact thermally until thermal equilibrium is reached. The initial thermal energy and the final thermal energy are the same since the energy is maintained during the contact.

The initial energy is and the final energy is . Equal both energies to get

-----------(3)

From equations (1) and , we can rewrite equation in the form

## Step 3: Law of energy

In order to verify that the final and starting energies are equal, you must apply the conservation law of energy. .