Question

number of photons absorbed in the solar cell of current density 46ma/cm square

Answer 1

hey mate!

This is called the generation current Jgen. In silicon, it is about 46 mA/cm2, i.e., there are about 1017 photons per cm2 per second absorbed in a Si solar cell.

Answer 2

The number of photons absorbed is $2.875$×$10^{17}$

Given:

The current density = $46mA/cm^{2}$

To Find:

The number of photons absorbed in the solar cell.

Solution:

As we know,

The charge of an electron is $1.6$×$10^{-19} C/electron$

Hence, the number of electrons in a 1 C charge is $\frac{1}{1.6X10^{-19} }$

$=6.25X10^{18}$ number of electrons/C.

Now, the number of electrons generated per $cm^{2}$ in current density of $46mA/cm^{2}$ will be equal to

$=6.25X10^{18} X (46X10^{-3} )\\= 2.875X10^{17}$

As each photon generates an electron after being absorbed, therefore the number of photons absorbed is equal to the number of electrons produced.

Therefore the number of photons absorbed is $= 2.875X10^{17}$