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Question
Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?
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Solution
According to Ohm’s law
V = IR
⇒ I = `V/R` …(1)
Now Potential difference is decreased to half
∴ New potential difference `"Vʹ" = V/2`
Resistance remains constant
So the new current `"Iʹ" = "Vʹ"/"R"`
= `(V/2)/R`
= `(1/2) (V/R)`
= `(1/2) I`
= `I/2`
Therefore, the amount of current flowing through the electrical component is reduced by half.
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