EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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an increase in the length of the wire
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an increase in the resistance of the wire
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an increase in the diameter of the wire
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an increase in the insulation around the wire
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Detailed explanation-1: -An increase in the length of the wire will cause an increase in the current flowing through the wire.
Detailed explanation-2: -To increase the current flowing in a circuit, the voltage must be increased, or the resistance decreased.
Detailed explanation-3: -The current in a copper wire is increased by increasing the potential difference between its end. Which one of the following statements regarding n, the number of charge carriers per unit volume in the wire and v the drift velocity of the charge carriers is correct-
Detailed explanation-4: -The resistance of a copper wire increases when the diameter decreases. Explanation: The resistance of copper is inversely proportional to the diameter of the wire hence when diameter decreases the resistance of a copper wire increases.
Detailed explanation-5: -From Equation 20.3, we see that doubling both the diameter and length causes the resistance of the wire to be reduced by a factor of 2.