Light Intensity versus Current (Concept Question)

[ShamTheCandle]

Hi.

Homework Statement

Consider the following scenario: On a partly cloudy day you find that a household PV array outputs 2.4 amps of current. If the clouds part and the sun comes out, exactly doubling the amount of light incident on the PV array, we should expect the array to output to be:

a)2.4 A
b)4.8 A
c)more than 4.8 A
d)less than 2.4 A
e)between 2.4 and 4.8 A

Homework Equations

I am not sure, if there is an equation between light intensity and current.

The Attempt at a Solution

Well, I am guessing the answer is b). It naturally makes sense to me. Is it right?
Can someone explain it to me using theory?

Thanks.

 

[jbsteele]

Yes, the answer is b) 4.8 A. The amount of current output from a photovoltaic (PV) array is directly proportional to the amount of light that is incident on the array. Therefore, if the light incident on the array is doubled, the current output will also be doubled.

 

[tomcue]

Hi there! You are correct in your guess that the answer is b) 4.8 A. Let me explain why using some theory.

Firstly, let's define light intensity and current. Light intensity is the amount of light energy that falls on a surface in a given time. Current, on the other hand, is the flow of electric charge through a conductor.

In the given scenario, we have a PV array that is converting light energy into electrical energy. This means that the light intensity incident on the array directly affects the amount of current it outputs. When the clouds part and the sun comes out, the light intensity incident on the array doubles. This increase in light intensity leads to an increase in the amount of light energy being converted into electrical energy, resulting in a higher output current.

To understand this concept better, we can look at the equation for current (I) in a circuit, which is I = V/R, where V is voltage and R is resistance. In this case, the voltage remains constant, as it is determined by the PV array's design. However, when the light intensity doubles, the resistance of the PV array decreases, resulting in an increase in current output.

Therefore, we can conclude that when the light intensity doubles, the current output of the PV array will also double, resulting in an output of 4.8 A. I hope this helps to clarify your understanding. Keep up the good work!