Advertisements
Advertisements
Question
Explain, why the potential difference across the terminals of a cell is more when the cell is not in use than it is when the cell is being used.
Advertisements
Solution
The reason is that when the cell is being used, there is a drop in potential across the internal resistance of the cell.
RELATED QUESTIONS
The p.d. across a 3 Ω resistor is 6 V. The current flowing in the resistor will be:
(a) `1/2A`
(b) 1 A
(c) 2 A
(d) 6 A
In the circuit diagram given below, three resistors R1, R2, and R3 of 5 Ω, 10 Ω and 30 Ω, respectively are connected as shown
Calculate:
- current through each resistor.
- total current in the circuit.
- total resistance in the circuit.
In the circuit shown below, the voltmeter reads 10 V.
(a) What is the combined resistance?
(b) What current flows?
(c) What is the p.d. across 2 Ω resistor?
(d) What is the p.d. across 3 Ω resistor?
State three factors on which the heat produced by an electric current depends. How does it depend on these factors?
Complete the following sentence:
A fuse is connected in ........... with the ......... wire.
An electric kettle has a heating element which is rated at 2 kW when connected to a 250 V electric supply. Calculate the
(a) Current which flows in the element when it is connected to a 250 V supply,
(b) Resistance of the filament,
(c) Heat produced in 1 minute by the element,
(d) Cost of running the kettle for 10 minutes a day for 30 days of the month, at the rate of Rs. 3.00 per unit.
An electric bulb is rated '100 W, 250 V'. How much current will the bulb draw if connected to a 250 V supply?
State whether the following statement is True or False:
The SI unit of charge is the coulomb.
State the condition when it is advantageous to connect cells in series.
