Chapter 5, Problem 65A

Interpretation Introduction

Interpretation: The monochromatic light shining on cesium metal is just above the threshold frequency is to be explained.

Concept Introduction: Single-wavelength light sources are known as monochromatic lights, where mono stands for only one chroma for color. The threshold frequency is a minimum frequency below which, regardless of the strength of the incident radiation, photoelectric emission is not possible.

Answer to Problem 65A

When the monochromatic light shining on the cesium metal is just slightly above the threshold frequency, the electrons are released with a low velocity.

Explanation of Solution

The photoelectric effect takes place when the frequency of light is higher than the threshold frequency.

Monochromatic light means the light of one frequency.

When the monochromatic light is just above the threshold frequency, the electrons will be emitted. The electron will be having low velocity.

Interpretation Introduction

Interpretation: The intensity of the light increases, but the frequency remains the same is to be explained.

Concept Introduction: Single-wavelength light sources are known as monochromatic lights, where mono stands for only one chroma for color. The threshold frequency is a minimum frequency below which, regardless of the strength of the incident radiation, photoelectric emission is not possible.

Answer to Problem 65A

A greater number of electrons are emitted at a low velocity when the intensity of the light is increased.

Explanation of Solution

The photoelectric effect takes place when the frequency of light is higher than the threshold frequency.

Since the intensity is increased, there is the emission of more electrons but at a low velocity.

Interpretation Introduction

Interpretation: Monochromatic light of a shorter wavelength is used is to be explained.

Concept Introduction: Single-wavelength light sources are known as monochromatic lights, where mono stands for only one chroma for color. The threshold frequency is a minimum frequency below which, regardless of the strength of the incident radiation, photoelectric emission is not possible.

Answer to Problem 65A

There is an emission of electrons at a faster velocity due to the usage of a shorter wavelength.

Explanation of Solution

The photoelectric effect takes place when the frequency of light is higher than the threshold frequency.

Monochromatic light means the light of one frequency.

The wavelength and frequency are inversely proportional to each other.

Since the shorter wavelength is used, that means the higher frequency, so the emission of electrons occurs with a high velocity.