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An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
- How much charge flows around the circuit each second?
- How much energy is transferred to the heater each second?
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An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
(b) How much energy is transferred to the heater each second?
Concept: undefined >> undefined
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An electric room heater draws a current of 2.4 A from the 120 V supply line. What current will this room heater draw when connected to 240 V supply line?
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What is nichrome? State its one use.
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Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
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Why are the coils of electric irons and electric toasters made of an alloy rather than a pure metal?
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How does the resistance of a wire vary with its:
diameter?
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Why is a series arrangement not used for connecting domestic electrical appliances in a circuit?
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An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
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Why does the connecting cord of an electric heater not glow hot while the heating element does?
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Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
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An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
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Explain why, tungsten is used for making the filaments of electric bulbs.
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Explain why, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.
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A heating coil has a resistance of 200 Ω. At what rate will heat be produced in it when a current of 2.5 A flows through it?
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A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
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Derive the expression for the heat produced due to a current 'I' flowing for a time interval 't' through a resistor 'R' having a potential difference 'V' across its ends. With which name is this relation known?
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How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
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The current passing through a room heater has been halved. What will happen to the heat produced by it?
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What is meant by the heating effect of current?
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