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Multiple Choice
When the current through a resistor is increased by a factor of 4, how does the power dissipated by the resistor change?
A
The power increases by a factor of 8.
B
The power increases by a factor of 16.
C
The power increases by a factor of 4.
D
The power remains the same.
Verified step by step guidance
1
Start by recalling the formula for power dissipated in a resistor: \( P = I^2 R \), where \( P \) is the power, \( I \) is the current, and \( R \) is the resistance.
Understand that the resistance \( R \) remains constant in this scenario, as the problem does not indicate any change in resistance.
Consider the change in current: the current \( I \) is increased by a factor of 4. This means the new current \( I' = 4I \).
Substitute the new current into the power formula: \( P' = (4I)^2 R = 16I^2 R \).
Compare the new power \( P' \) with the original power \( P = I^2 R \). The new power is \( 16 \) times the original power, indicating that the power increases by a factor of 16.