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A block of metal of mass 1.5 kg which is suitably insulated is heated from 30 0C to 50 0C in 8 minutes and 20 seconds by an electric heater coil rated 54 watts. Find; a) The quantity of heat supplied by the heater b) The heat capacity of the block c) Its specific heat capacity

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A block of metal of mass 1.5 kg which is suitably insulated is heated from 30 0C to 50 0C in 8 minutes and 20 seconds by an electric heater coil rated 54 watts.

Find;

a) The quantity of heat supplied by the heater

b) The heat capacity of the block

c) Its specific heat capacity

An electric light bulb has a filament of resistance 470 Ω. The leads connecting the bulb to the 240 V mains have a total resistance of 10 Ω. Find the power dissipated in the bulb and in the leads.

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An electric light bulb has a filament of resistance 470 Ω.

The leads connecting the bulb to the 240 V mains have a total resistance of 10 Ω. Find the power dissipated in the bulb and in the leads.

What is the maximum number of 100 W bulbs which can be safely run from a 240 V source supplying a current of 5 A?

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What is the maximum number of 100 W bulbs which can be safely run from a 240 V source supplying a current of 5 A?

A heating coil providing 3,600 J/min is required when the p.d across it is 24 V. Calculate the length of the wire making the coil given that its cross-sectional area is 1 × 10-7 m2 and resistivity 1 × 10-6 Ω m.

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A heating coil providing 3,600 J/min is required when the p.d across it is 24 V. Calculate the length of the wire making the coil given that its cross-sectional area is 1 × 10-7 m2 and resistivity 1 × 10-6 Ω m.

An iron box has a resistance coil of 30 Ω and takes a current of 10 A. Calculate the heat in kJ developed in 1 minute.

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An iron box has a resistance coil of 30 Ω and takes a current of 10 A. Calculate the heat in kJ developed in 1 minute.

A capacitor of two parallel plates separated by air has a capacitance of 15pF. A potential difference of 24 volts is applied across the plates, a) Determine the charge on the capacitors. b) When the space is filled with mica, the capacitance increases to 250pF. How much more charge can be put on the capacitor using a 24 V supply?

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A capacitor of two parallel plates separated by air has a capacitance of 15pF.

A potential difference of 24 volts is applied across the plates,

a) Determine the charge on the capacitors.

b) When the space is filled with mica, the capacitance increases to 250pF.

How much more charge can be put on the capacitor using a 24 V supply?

A battery consists of two identical cells, each of e.m.f 1.5 v and internal resistance of 0.6 Ω, connected in parallel. Calculate the current the battery drives through a 0.7 Ω resistor.

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A battery consists of two identical cells, each of e.m.f 1.5 v and internal resistance of 0.6 Ω, connected in parallel. Calculate the current the battery drives through a 0.7 Ω resistor.

. A cell drives a current of 0.6 A through a resistance of 2 Ω. if the value of resistance is increased to 7 Ω the current becomes 0.2 A. calculate the value of e.m.f of the cell and its internal resistance.

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. A cell drives a current of 0.6 A through a resistance of 2 Ω. if the value of resistance is increased to 7 Ω the current becomes 0.2 A.

calculate the value of e.m.f of the cell and its internal resistance.

Given that the resistivity of nichrome is 1.1× 10-6Ωm, what length of nichrome wire of diameter 0.42 mm is needed to make a resistance of 20 Ω?

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Given that the resistivity of nichrome is 1.1× 10-6Ωm, what length of nichrome wire of diameter 0.42 mm is needed to make a resistance of 20 Ω?

A wire of resistance 20Ω is connected across a battery of 5 V. What current is flowing in the circuit?

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A wire of resistance 20Ω is connected across a battery of 5 V. What current is flowing in the circuit?