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प्रश्न
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उत्तर
This is done to protect the appliances and circuits from any damage due to short-circuit and thus accidents like fire and fatal shocks. Earthing provides an easy and safe path to the excess current in the circuit and sends it to the ground.
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संबंधित प्रश्न
Three 2 V cells are connected in series and used as a battery in a circuit.
How many joules of electrical energy does 1 C gain on passing through (i) one cell (ii) all three cells?
If the current through a floodlamp is 5 A, what charge passed in 10 seconds?
(a) 0.5 C
(b) 2 C
(c) 5 C
(d) 50 C
Consider the circuit given below when A, B and C are three identical light bulbs of constant resistance. 
(a) List the bulbs in order of increasing brightness.
(b) If C burns out, what will be the brightness of A now compared with before?
(c) If B burns out instead, what will be the brightness of A and C compared with before?
A wire of length 5 m has a resistance of 2.0 Ω calculate:
(a) the resistance of wire of length 1 m
(b) the equivalent resistance if two such wires each of length 2 m are joined in parallel.
(c) the resistance of 1 m length of wire of same material but of half diameter.
Electrical appliances have voltage and power ratings as listed below. Which
has the larger working resistance?
| Appliances | Voltage (V) | Power (W) |
| (a) Washing machine | 250 | 3000 |
| ( b) Television | 240 | 160 |
| (c)240 | 240 | 1500 |
| ( d) Hair curler | 250 | 20 |
| ( e) Car head lamp | 12 | 36 |
State the condition when it is advantageous to connect cells in parallel.
Kilowatt hour is the unit of
A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross section of the filament in 16 seconds would be roughly
