Chapter 7, Problem 7.63P

(a)

Interpretation Introduction

Interpretation:

The reason the lines for potassium and silver do not begin at the origin in the kinetic energy vs frequency graph is to be determined.

Concept introduction:

The major points of the Einstein photoelectric effect are as follows:

1) Light consists of photons. Each photon has an energy equivalent to $h\nu$.

2) The collision of a photon and an electron on the metal surface is elastic in nature.

3) Out of the total energy gained by the electron, some of it is used by the electron to lodge out of the metal surface whereas the remaining part is the kinetic energy of the electron.

4) The minimum energy required to lodge an electron out of the metal surface is called the work function of the metal.

5) The remaining energy is the maximum kinetic energy of the photoelectron.

(b)

Interpretation Introduction

Interpretation:

The reason the lines for potassium and silver do not begin at the same point is to be determined.

Concept introduction:

The major points of the Einstein photoelectric effect are as follows:

1) Light consists of photons. Each photon has an energy equivalent to $h\nu$.

2) The collision of a photon and an electron on the metal surface is elastic in nature.

3) Out of the total energy gained by the electron, some of it is used by the electron to lodge out of the metal surface whereas the remaining part is the kinetic energy of the electron.

4) The minimum energy required to lodge an electron out of the metal surface is called the work function of the metal.

5) The remaining energy is the maximum kinetic energy of the photoelectron.

(c)

Interpretation Introduction

Interpretation:

The metal from which electron will be ejected by the light of shorter wavelength is to be determined.

Concept introduction:

Electromagnetic waves are radiations that are formed by oscillating electric and magnetic fields. The electric and magnetic field components of an electromagnetic wave are perpendicular to each other.

Energy is proportional to the frequency and is expressed by the Plank-Einstein equation as follows:

$E=h\nu$

Here,

$E$ is the energy.

$h$ is the Plank’s constant.

$\nu$ is the frequency.

The equation to relate the frequency and wavelength of electromagnetic radiation is as follows:

$\nu =\frac{c}{\lambda }$

The equation to calculate the energy of a photon is,

$E=h\frac{c}{\lambda }$

Here,

$c$ is the speed of light.

$\lambda$ is the wavelength.

(d)

Interpretation Introduction

Interpretation:

The reason the slopes are equal for both potassium and silver is to be determined.

Concept introduction:

The major points of the Einstein photoelectric effect are as follows:

1) Light consists of photons. Each photon has an energy equivalent to $h\nu$.

2) The collision of a photon and an electron on the metal surface is elastic in nature.

3) Out of the total energy gained by the electron, some of it is used by the electron to lodge out of the metal surface whereas the remaining part is the kinetic energy of the electron.

4) The minimum energy required to lodge an electron out of the metal surface is called the work function of the metal.

5) The remaining energy is the maximum kinetic energy of the photoelectron.