Experiment 3 — Choose the Right Fuse

Topic: Physics · Class 10 · Heating effect of current, electric power and energy

Aim: Run the 2 kW geyser safely on a 220 V supply with the correct fuse .

Daily: Every bill you pay is in kilowatt-hours, and every fuse in your meter box is chosen by exactly this calculation. Using too large a fuse is a genuine fire risk.

Question: A 2000 W geyser on 220 V draws about…

Exp: I = P ÷ V = 2000 ÷ 220 ≈ 9.1 A.

Question: The commercial unit of electrical energy is the…

Question: Joule’s law of heating states H =

Exp: Heat rises with the square of the current.

Question: Fitting a much larger fuse than needed is dangerous because…

Exp: The fuse must be the weakest link.

Question: The earth wire is provided to…

Exp: It protects users of metal-bodied appliances.