# Find the frequency of a photon with a wavelength of 20nm

## Answers

Option (b) is the correct.

Explanation:

It is known that energy is directly proportional to frequency.

Mathematically, [tex]E \propto \nu[/tex]

or, E = [tex]h \times \nu[/tex] ............ (1)

where, E = energy

h = Plank's constant

[tex]\nu[/tex] = frequency

This relation shows that higher is the energy then more will be the frequency of electrmagnetic radiation.

Also, [tex]\nu = \frac{c}{\lambda}[/tex] ......... (2)

where, c = speed of light

[tex]\lambda[/tex] = wavelength

Therefore, substituting value of [tex]\nu[/tex] from equation (2) into equation (1) as follows.

E = [tex]h \times \nu[/tex]

E = [tex]h \times \frac{c}{\lambda}[/tex]

This relation shows that higher is the energy then lower will be the wavelength.

Thus, we can conclude that as the energy of a photon increases, its frequency decreases, is incorrect statement.

1.89x10^15s₋1

Explanation:

the relationship between frequency and wavelength is given as

c= frequency x wavelength

where c = speed of light - 3.8 x 10 ^8 m/s

given here that wavelength = 159 nm

changing to m becomes 1m= 10⁻9nm,

159nm becomes 159 x10-9m

therefore our frequency will now be

frequency = speed of light (c)/ wavelength

= 3.8x1`0^8/159x10^-9 =1.886 x10^15s⁻1 = 1.89 x10^15s⁻1

[tex]Frequency=2.88\times 10^{14}\ s^{-1}[/tex]

Explanation:

The relation between frequency and wavelength is shown below as:

[tex]c=frequency\times Wavelength [/tex]

c is the speed of light having value [tex]3\times 10^8\ m/s[/tex]

Given, Wavelength = 1040 nm

Also, 1 m = [tex]10^{-9}[/tex] nm

So,

Wavelength = [tex]1040\times 10^{-9}[/tex] m

Thus, Frequency is:

[tex]Frequency=\frac{c}{Wavelength}[/tex]

[tex]Frequency=\frac{3\times 10^8}{1040\times 10^{-9}}\ s^{-1}[/tex]

[tex]Frequency=2.88\times 10^{14}\ s^{-1}[/tex]

Answer

[tex]Frequency=1.887*10^15s-1[/tex]

Explanation:

Frequency reffers to the number of occurrences of a repeating event per unit of time. It is measured in units of hertz (Hz), it can also be measured as occurrence of a repeating event per second as well

c is the speed of light having value 3*10^8m/s

Given, Wavelength = 159 nm

But n= 10^-9m

Wavelength=159*10^-9

C=frequency* wavelength

Frequency=c/wavelength

Frequency= 3*10^8/159*10^-9

[tex]Frequency=1.887*10^15s-1[/tex]

Frequency = 0.8×10¹⁵ Hz

Explanation:

Given data:

Frequency of photon = ?

Wavelength of photon = 3.75 ×10⁻⁷ m

Solution:

Formula:

Speed of photon = wavelength × frequency

Frequency = speed of photon / wavelength

Now we will put the values in formula.

Frequency = 3 ×10⁸ m/s / 3.75 ×10⁻⁷ m

Frequency = 0.8×10¹⁵ s⁻¹

s⁻¹ = Hz

Frequency = 0.8×10¹⁵ Hz

F = c ÷ λ

= (3 x 10^8)/100

= 3 x 10^6 Hz