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?
According to ohm's law we know that current is directly potential to the potential difference across the two ends.
V = IR
Here, R= Resistance of the electrical component
V= Potential difference and I=Current
The potential difference is reduced by half, keeping resistance constant.
Let the new resistance be R' and the new amount of current be I '.
Therefore, from Ohm’s law, we obtain the amount of new current.
So, the amount of current flowing through the electrical component is reduced by half.
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(b) Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
(c) Why is the series arrangement not used for domestic circuits?
(d) How does the resistance of a wire vary with its area of cross-section?
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(b) aldehyde.
(c) ketone.
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(c) Goat, cow and elephant
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