Chapter 22, Problem 48A

Wrap a piece of paper around a thick metal bar and place it in a flame. Note that the paper will not catch fire. Can you figure out why? (Hint: Paper generally will not ignite until its temperature reaches about $230°C$.)

To determine

Radiation usually passes through gases more easily than through solids and liquids

Explanation of Solution

Introduction:

Radiation is that the transfer of energy by electromagnetic waves. They carry energy through solids, liquids, and gases. But they will also carry energy through empty space. Energy transferred by radiation is usually called energy.

When we sit back a hearth, we feel warm because heat is transferred by radiation from the hearth to our skin.

Radiant energy can travel through the space between particles during a solid, liquid, or gas. Particles can absorb the radiation and emit a number of the energy they absorbed. This energy then travels through the space between particles. it's absorbed and emitted by other particles.

The transfer of energy by radiation works best with gases. The particles in gases are much farther apart than in solids or liquids. This extra space allows the energy to travel more easily through gases.

Conclusion:

Radiation from the Sun is important to life on Earth, but ultraviolet from the Sun also can be very damaging for our skin. it's better to avoid direct sunlight between 11 am and a couple of pm.