Samacheer Kalvi solutions for Science [English] Class 10 SSLC TN Board chapter 4 - Electricity [Latest edition]

Which of the following is correct?

SI unit of resistance is:

In a simple circuit, why does the bulb glow when you close the switch?

Kilowatt hour is the unit of

When a circuit is open, _____ cannot pass through it.

The ratio of the potential difference to the current is known as ________.

The wiring in a house consists of ______ circuits.

The power of an electric device is a product of ______ and ______.

LED stands for ______.

Ohm’s law states the relationship between power and voltage.

MCB is used to protect household electrical appliances.

The SI unit for electric current is the coulomb.

One unit of electrical energy consumed is equal to 1000 kilowatt-hour.

The effective resistance of three resistors connected in series is lesser than the lowest of the individual resistances.

Match the items in column-I to the items in column-II:

Mark the correct choice

1. Assertion: Electric appliances with a metallic body have three wire connections.
2. Reason: Three-pin connections reduce the heating of the connecting wires.

Mark the correct choice

1. Assertion: In a simple battery circuit the point of highest potential is the positive terminal of the battery.
2. Reason: The current flows towards the point of the highest potential

Mark the correct choice

1. Assertion: LED bulbs are far better than incandescent bulbs.
2. Reason: LED bulbs consume less power than incandescent bulbs.

Define the unit of current.

What happens to the resistance, as the conductor is made thicker?

Why is tungsten metal used in bulbs, but not infuse wires?

Name any two devices, which are working on the heating effect of the electric current.

Define electric potential and potential difference.

What is the role of the earth wire in domestic circuits?

State Ohm’s law.

Distinguish between the resistivity and conductivity of a conductor.

What connection is used in domestic appliances and why?

With the help of a circuit diagram derive the formula for the resultant resistance of three resistances connected:

1. in series and
2. in parallel

1. What is meant by electric current?
2. Name and define its unit.
3. Which instrument is used to measure the electric current? How should it be connected in a circuit?

State Joule’s law of heating.

An alloy of nickel and chromium is used as the heating element. Why?

How does a fuse wire protect electrical appliances?

Explain about domestic electric circuits. (circuit diagram not required)

What are the advantages of LED TV over the normal TV?

List the merits of the LED bulb.

An electric iron consumes energy at the rate of 420 W when heating is at the maximum rate and 180 W when heating is at the minimum rate. The applied voltage is 220 V. What is the current in each case?

A 100-watt electric bulb is used for 5 hours daily and four 60 watt bulbs are used for 5 hours daily. Calculate the energy consumed (in kWh) in the month of January.

A torch bulb is rated at 3 V and 600 mA. Calculate it’s

1. power
2. resistance
3. energy consumed if it is used for 4 hours.

A piece of wire having a resistance R is cut into five equal parts.

1. How will the resistance of each part of the wire change compared with the original resistance?
2. If the five parts of the wire are placed in parallel, how will the resistance of the combination change?
3. What will be ratio of the effective resistance in series connection to that of the parallel connection?

Two resistors when connected in parallel give the resultant resistance of 2 ohms, but when connected in series the effective resistance becomes 9 ohms. Calculate the value of each resistance.

How many electrons are passing per second in a circuit in which there is a current of 5 A?

A piece of wire of resistance 10 ohm is drawn out so that its length is increased to three times its original length. Calculate the new resistance.