An electric heater uses a resistance wire of resistance 24 Ω24\ \Omega24 Ω. The power dissipated in the resistance wire is 2200 W2200\text{ W}2200 W.
Calculate the current in the resistance wire.
The resistance wire of the heater has a length of 1.6 m1.6\text{ m}1.6 m and a cross-sectional area of 6.0×10−7 m26.0 \times 10^{-7}\text{ m}^26.0×10−7 m2.
A new heater is designed using wire of the same material with length 2.4 m2.4\text{ m}2.4 m and cross-sectional area 4.5×10−7 m24.5 \times 10^{-7}\text{ m}^24.5×10−7 m2.
Calculate the resistance of this wire.
The 2200 W2200\text{ W}2200 W heater is used in a country where electricity costs 0.250.250.25 dollars per kilowatt-hour.
Calculate the cost of using the heater continuously for three days.
69 exam-style questions on CIE IGCSE Physics 4.2.5 Electrical energy and electrical power. Each one has a worked solution and a mark scheme showing where the marks go.