Question

Let the resistance of an electrical device remain constant, while the potential difference across its two ends decreases to one fourth of its initial value. What change will occur in the current through it? State the law which helps us in solving the above stated question. 

Answer 1

The change in the current flowing through the electrical component can be determined by Ohm's Law.

According to ohm's law i.e.,

V = IR

V: applied voltage

I: current

R: resistance

⇒ I = `"V"/"R"`

Now potential difference becomes one fourth,

V' = `"V"/4`

So current will be:  I' =`(("V"//4))/"R"` 

⇒ I' = `"v"/(4"R")`

⇒ I' = `"I"/4`                                     

When the potential difference is one fourth, the current through the component also decreases to one fourth of its initial value.