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प्रश्न
The voltage applied to a given rheostat is made four times its initial value. By what factor will be resistance of the rheostat change?
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उत्तर
The resistance of the rheostat will not change at all as it does not depend on the voltage applied across it.
संबंधित प्रश्न
An electrical appliance has a resistance of 25 Ω. When this electrical appliance is connected to a 230 V supply line, the current passing through it will be:
(a) 0.92 A
(b) 2.9 A
(c) 9.2 A
(d) 92 A
Write down an expression for the resistance of a metallic wire in terms of the resistivity.
If five resistances, each of value 0.2 ohm, are connected in series, what will be the resultant resistance?
What is the resistance between A and B in the figure given below?
What do you mean by power rating of an electrical appliance? How do you use it to calculate
(a) the resistance of the appliance and
(b) the safe limit of the current in it, while in use?
Why are thick copper wires used as connecting wires?
Three resistors of 6Ω, 3Ω and 2Ω are connected together so that their total resistance is greater than 6Ω but less than 8Ω Draw a diagram to show this arrangement and calculate its total resistance.
In the circuit shown below, calculate the equivalent resistance between the points (i) A and B, (ii) C and D.
Two resistors having 2Ω and 3Ω resistance are connected—(i) in series, and (ii) in parallel. Find the equivalent resistance in each case.
Two wires of the same length and area made of two materials of resistivity ρ1 and ρ2 are connected in series to a source of potential V. The equivalent resistivity for the same area is:
