Three resistors R1, R2 and R3 (R1 > R2 > R3) are connected to a battery of voltage V such that the circuit generates maximum heat per unit time. Which one among the following is the correct circuit combination for this?
R1, R2 and R3 are connected in parallel combination
For a fixed voltage V, power (heat per unit time) dissipated equals V²/R_equivalent, so heat is maximised when the equivalent resistance of the combination is minimised. Connecting all three resistors in parallel always yields the smallest possible equivalent resistance obtainable from three resistors, smaller than any mixed series-parallel arrangement such as option (c) or (d). Hence connecting R1, R2 and R3 all in parallel maximises the heat generated per unit time.
A parallel-plate capacitor, with air in between the plates, has capacitance C. Now the space between the two plates of the capacitor is filled with a dielectric of dielectric constant 7. Then the value of the capacitance will become
An electric bulb is connected to a 110 V generator. The current is 0.2 A. What is the power of the bulb ?
The r.m.s. potential difference between the red live wire and black neutral wire in Indian domestic electric supply is
A parallel-plate capacitor of capacitance C 1is made using two gold plates. Another parallel-plate capacitor of capacitance C 2is made using two aluminium plates with same plate separation, and all the four plates are of same area. If ρ gand ρ aare respectively the electrical resistivity of gold and aluminium, then which one of the following relations is correct?
Two metallic wires made from copper have same length but the radius of wire 1 is half of that of wire 2. The resistance of wire 1 is R. If both the wires are joined together in series, the total resistance becomes
Three resistors of resistances 11 Ω, 22 Ω and 33 Ω are connected in parallel. Their equivalent resistance is equal to
Which of the following is a bad conductor of electricity?
In general, in an alternating current circuit
The laws of electromagnetic induction have been used in the construction of a
A 220 volt and 100 watt bulb is connected to a 110 volt source. The power consumption by the bulb is
Which of the following statement is correct?
I. 1 kWh = 3.6 × 10 6J.
II. The SI unit of electric current is the ampere.