Explain the meaning of the statement 'the current rating of a fuse is 5 A'.
[8] Current Electricity
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'A fuse is rated 8 A'. Can it be used with an electrical appliance of rating 5 kW, 200 V?
[8] Current Electricity
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An electric kettle is rated 3 kW, 250 V. Give reason whether this kettle can be used in a circuit which contains a 13 A fuse.
[8] Current Electricity
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Calculate the electric current supplied by a 12 V battery of an automobile to a starter that develops a power of 2.4 kW.
[8] Current Electricity
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A 720 W heater operates from a 220 V line voltage. Calculate:
(a) The electrical energy consumed by the heater in 3 h.
(b) The cost of electrical energy consumption at the rate of 60 paise per kWh.
[8] Current Electricity
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What is fuse? Name the material of fuse.
[8] Current Electricity
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State two characteristics of a fuse wire.
[8] Current Electricity
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Complete the following sentence:
A fuse is a short piece of wire of high ......... and low
[8] Current Electricity
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Complete the following sentence:
A fuse is connected in ........... with the ......... wire.
[8] Current Electricity
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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 ...........
[8] Current Electricity
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Calculate the amount of energy transferred by a 10 A electric current flowing through a resistor of 5 o for 15 minutes.
[8] Current Electricity
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A 200 v electric transfer draws an electric current of 11 A. What is its electrical resistance?
[8] Current Electricity
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Where is the main fuse in a house circuit connected?
[8] Current Electricity
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Is kWh the unit of electrical energy?
[8] Current Electricity
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What is the purpose of a switch in a circuit? Why is the switch put in the live wire?
[8] Current Electricity
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A switch is not touched with wet hands while putting it on or off. Give a reason for your answer.
[8] Current Electricity
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An electric bulb is rated 250 W, 230 V. What information does this convey? Calculate the current through a 60 W lamp rated for 250 V. If the line voltage falls to 200 V, how is the power consumed by the bulb affected?
[8] Current Electricity
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The metal case of an electric appliance is earthed. Explain the reason.
[8] Current Electricity
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A bulb marked 12 V, 24 W operates on a 12 volt car battery for 20 minutes. Calculate:
(i) The current flowing through it, and
(ii) The energy liberated.
[8] Current Electricity
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What is international convention of colour coding in a cable?
[8] Current Electricity
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