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प्रश्न
Name two devices which work on the heating effect of electric current.
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उत्तर
The two devices that work on the heating effect of electric current are a bulb and an electric fuse.
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संबंधित प्रश्न
The SI unit of charge is volt.
The work done in moving a unit charge across two points in an electric circuit is a measure of:
(a) current
(b) potential difference
(c) resistance
(d) power
A car headlight bulb working on a 12 V car battery draws a current of 0.5 A. The resistance of the light bulb is:
(a) 0.5 Ω
(b) 6 Ω
(c) 12 Ω
(d) 24 Ω
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?
The lamps in a house hold circuit are connected in parallel because:
(a) this way they required less current
(b) if one lamp fails the others remain lit
(c) this way they require less power
(d) if one lamp fails the other also fail
Using the circuit given below, state which of the following statement is correct?
(a) When S1 and S2 are closed, lamps A and B are lit.22
(b) With S1 open and S2 closed, A is lit and B is not lit.
(c) With S2 open and S1 closed A and B are lit.
(d) With S1 closed and S2 open, lamp A remains lit even if lamp B gets fused.
Which effect of current is utilised in the working of an electric fuse?
Three resistors of 6.0 𝛀, 2.0𝛀 and 4.0𝛀 are joined to an ammeter A and a cell of e.m.f. 6.0 V as
shown in fig 8.52 Calculate:
(a) the effective resistance of the circuit and
(b) the reading of ammeter.
Complete the following sentence:
Fuse wire has a ............ Melting point and it is made of an alloy of ......... and if the current in a circuit rises too high, the fuse wire ...........
What is international convention of colour coding in a cable?
What would be the danger involved in replacing a blown fuse with the one which would carry a large current?
An electric oven is rated as 1.5 kW, 250 V. If it is connected to a 250 V mains, calculate the
(a) Current drawn,
(b) Energy consumed in 20 hours,
(c) Cost of energy consumed in 20 hours at the rate of Re. 1 per unit.
Name the principle on which a transformer works.
State whether true or false. If false, correct the statement.
Current can produce magnetic field.
Electric current passes through a metallic conductor due to the movement of ______.
1020 electrons, each having a charge of 1.6 x 10-19 C, flows in a circuit V is 0.1s. What is the current in ampere?
