Chapter 33, Problem 2Q

To determine

In equilibrium condition, a star will generates all the energy from the core when it radiates at its surface. Explain what will happen if it radiates more or less energy than is normal radiation.

Answer to Problem 2Q

Solution:

When a star begins to generate more energy than it radiates, there is an increase in the energy of the gas atoms that make up the star. This increases the speed of the atoms, which results in an increase in temperature. As the temperature increases, the radiant energy from the star increases and it gets back to an equilibrium state.

When the energy being generated is less than the energy being radiated, the gravitational pull of the star on its atoms causes the star to decrease in size. This increases pressure, increasing the energy being generated, resulting in equilibrium again.

Explanation of Solution

The star which is visible to the naked eye and which is closer to the earth is Sun. Other the Sun we can see many other star during night and it will appear to be a fixed luminous points in the sky because they are far way from the earth. A star is a luminous spheroid body of plasma bind together by its own gravity.