(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

State three factors on which the heat produced in a metallic wire due to passage of current in it depends.

An electric current is passed through a metallic wire. The wire gets heated up. Give the reason. Is it possible to melt the wire by passing a heavy current?

Why is heating coil wound in the form of a helix in electric stove?

What are the two main systems of wiring commonly used in houses? Which of these systems mentioned by you is better and why?

Point out two main disadvantages of ‘Tree System’.

Name three main characteristics of an heating element.

Mention three uses of the carbon arc.

Name two common material used for heating elements.

In an electric radiator or room heater, state with reason, why the porcelain tube wound with a nichrome wire is placed between the pole and principal focus of the parabolic concave reflector.

Why is heating element wound on a long porcelain rod in a room heater.

Why is a concave reflector placed behind the heating element in a room heater.

State the position of heating element with respect to principal focus of concave reflector and give reason for choosing this position.

Household wiring for lamp connections can either be done in parallel or in series.Which one would you prefer? Give a reason for your answer.

Why is the heating element of an electric oven wound on a helix? State the reason.

The electric bulbs used these days have a coil-coiled filament. State its reason.

What changes in energy occur in an electric bulb?

What changes in energy occur in an electric heater?

An electric filament lamp is connected to a supply of voltage higher than the recommended value. Give reasons, why compared with a normal performance, the lamp emits a brighter light and its life is shortened.

‘The current rating of a fuse is 5A’. Comment on this statement.

Two lamps are rated 220V, 50W and the other rated 220V, 100W are connected in series with the mains of 220 V. Explain, why the 50W lamp glows more?