The momentum of a photon of energy will be

Options

A. hv
B. hv/c
C. hvc
D. h/v

Explanation

To find the momentum of a photon in terms of its energy, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the relationship between energy and momentum of a photon:**
The energy \( E \) of a photon is related to its frequency \( \nu \) by the equation:
\[ E = h \nu \]
where \( h \) is Planck's constant.

2. **Use the relationship between wavelength and momentum:**
The momentum \( p \) of a photon can be expressed in terms of its wavelength \( \lambda \):
\[ p = \frac{h}{\lambda} \]

3. **Relate wavelength to energy:**
The speed of light \( c \) is related to wavelength and frequency by the equation:
\[ c = \lambda \nu \]
Rearranging this gives:
\[ \lambda = \frac{c}{\nu} \]

4. **Substitute the expression for wavelength into the momentum equation:**
Substituting \( \lambda \) into the momentum equation gives:
\[ p = \frac{h}{\lambda} = \frac{h \nu}{c} \]

5. **Express momentum in terms of energy:**
Since \( E = h \nu \), we can substitute \( \nu \) in terms of energy:
\[ \nu = \frac{E}{h} \]
Substituting this into the momentum equation:
\[ p = \frac{h \left(\frac{E}{h}\right)}{c} = \frac{E}{c} \]

6. **Final expression for momentum:**
Therefore, the momentum of a photon in terms of its energy \( E \) is:
\[ p = \frac{E}{c} \]

### Final Answer:
The momentum of a photon of energy \( E \) is given by:
\[ p = \frac{E}{c} \]