Chapter 5, Problem 14STP

Interpretation Introduction

Interpretation: The drawing showing the electromagnetic wave with the highest amplitude needs to be identified.

Concept Introduction: When an electric field and a magnetic field are coupled together, an electromagnetic wave is formed. Here, electric and magnetic fields are perpendicular to each other as well as the direction of the wave.

Here, the wavelength of a wave is defined as the distance between two successive crests and troughs. The frequency of a wave is the number of waves passing a point in one second. The amplitude of a wave is determined by the height of the crests and troughs formed in the electromagnetic waves.

Moreover, the energy of the wave is inversely proportional to its wavelength. This can be explained by the following formula:

  $E=\frac{hc}{\lambda }$

Here, h is Planck’s constant and c is the speed of light. Both are constant; thus, the above relation can be rewritten as follows:

  $E\propto \frac{1}{\lambda }$

Here, E is energy and $\lambda$ is the wavelength of light.

Answer to Problem 14STP

Correct answer is option (C).

Explanation of Solution

Reason for correct option:

The amplitude of the wave is the height of crests and troughs formed in the wave. From the drawings, it is clear that a wave with maximum height is given in option (C).

  

Thus, it is the correct option.

Conclusion

Reason for incorrect options:

The drawings of waves in option (A) and (B) are as follows:

  

  

Here, the height is low as compared to the wave in option (C) thus, these waves have low amplitudes as compared to the wave in option (C).

Thus, options (A) and (B) are incorrect.