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

Write the seven prominent colours present in white light spectrum in order of their increasing wavelength.

Name the seven prominent colours of the white light spectrum in order of their increasing frequencies.

Name four colours of the spectrum of white light which have wavelength longer than blue light.

State whether the current is a scalar or vector?

Electrical power P is given by the expression P = (Q × V) ÷ time

(a) What do the symbols Q and V represent?

(b) Express the power P in terms of current and resistance explaining the meanings of symbols used there in.

State the S.I. units of electrical power.

Define the term kilowatt - hour and state its value in S.I. unit.

1 kWh = `(1 "volt" xx 1 "ampere" xx "_________")/1000`

Complete the following:

1 kWh = _________ J

An electric bulb is marked '100 W, 250 V'. What information does this convey?

Calculate the current through a 60 W lamp rated 250 V. If the line voltage falls to 200 V, how is power consumed by the bulb affected?

An electric bulb is rated '100 W, 250 V'. How much current will the bulb draw if connected to a 250 V supply?

An electric bulb is rated at 220 V, 100 W.

1. What is its resistance?
2. What safe current can be passed through it?

A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.

An electric iron is rated 750 W, 230 V. Calculate the electrical energy consumed by the press in 16 hours.

A bulb marked 12 V, 24 W operates on a 12 V battery for 20 minutes. Calculate:

1. The current flowing through it, and
2. The energy consumed.

A current of 0.2 A flows through a wire whose ends are at a potential difference of 15 V. Calculate:

(i) The resistance of the wire, and

(ii) The heat energy produced in 1 minute.

An electric bulb is rated 250 W, 230 V. 

1. the energy consumed in one hour, and
2. the time in which the bulb will consume 1.0 kWh energy when connected to 230 V mains.

Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. Calculate :

The total current taken from the supply

Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. The resistance of each heater