An alternating potential difference is connected across a pure resistor and the frequency of the supply is varied, keeping the r.m.s voltage constant. The mean rate of production of heat in the resistor is:
Correct answer: A. Proportional to (frequency)2
- A. Proportional to (frequency)2
- B. Proportional to frequency
- C. Proportional to (frequency)½
- D. Independent to frequency
Explanation
a) Proportional to (frequency)^2:The rate of production of heat in a pure resistor, when connected to an alternating potential difference, is determined by the square of the frequency. This is because the power dissipated in a resistor is given by the equation P = I^2 * R, where I is the current flowing through the resistor and R is the resistance. In an AC circuit, the current is proportional to the frequency, so the power, and therefore the rate of heat production, is proportional to the square of the frequency.
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About AC Through Resistor, Capacitor and Inductor
Alternating current through a resistor, capacitor and inductor involves phase relationships between voltage and current, reactance, impedance and energy transfer. A resistor keeps voltage and current in phase, while a capacitor and inductor produce opposite phase shifts, a distinction used in circuit diagrams and numerical calculations.
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