Why does the cord of an electric heater not glow while the heating element does?

An electric heater with a power rating of 2 kW is operated for 3 hours daily for the entire month of April. If the cost of electricity is Rs 6 per unit, what is the total electricity bill for the month? (Assume April has 30 days)

Assertion (A): Tungsten metal is used for making the filament of incandescent electric lamps. Reason (R): Tungsten has a very high melting point and produces light at high temperatures without melting.

Explain why the main power supply line coming into a house typically uses a thicker gauge copper wire compared to the thinner wires used for individual appliance connections within the house.

Two electric bulbs, rated 100W, 220V and 60W, 220V respectively, are connected in series to a 220V supply. Which bulb will glow brighter and why?

A circuit consists of three resistors: R1, R2, and R3. R1 = 5 Ω is connected in series with the parallel combination of R2 = 10 Ω and R3 = 10 Ω. If this circuit is connected to a 12V battery, what is the power dissipated across R1?

Explain why household electrical appliances are always connected in parallel with the main supply and not in series.

Assertion (A): Nichrome alloy is extensively used in the heating elements of electrical appliances like toasters and electric irons. Reason (R): Nichrome has a very high resistivity and a high melting point, making it suitable for producing significant heat without melting.

An electric heater is rated at 2.2 kW and operates on a 220 V household supply. What is the minimum rating of the fuse that should be used in the circuit to protect the heater?

A metallic wire of resistance R is stretched uniformly so that its new length becomes twice its original length. Assuming that its volume remains constant during stretching, what will be its new resistance?

A household circuit consists of two resistors, R1 = 6 Ω and R2 = 3 Ω, connected in parallel. This parallel combination is then connected in series with a third resistor, R3 = 8 Ω. If the entire circuit is connected to a 20 V battery, what is the current flowing through resistor R2?

The resistance of a circuit component is constant. If the voltage across it is halved, the current through it will:

The resistance of a conductor is 5 Ohm. If a current of 2A flows through it, the potential difference across its ends is:

A conductor has 10²0 free electrons passing through a cross-section in 2 seconds. The current flowing is:

If the voltage across a resistor is 10V and the current flowing is 2A, the power dissipated by the resistor is:

Which of the following is not a property of electric field lines?

How many joules are there in 1 calorie?

The formula for electric energy consumed (E) is:

A 100W bulb and a 40W bulb are connected in parallel to a 220V supply. Which bulb will glow brighter?

A 100W bulb and a 40W bulb are connected in series to a 220V supply. Which bulb will glow brighter?

Which of these is the most suitable material for a heating element?

What happens to the resistance of a conductor if its area of cross-section is increased?

The reciprocal of resistance is called:

In a parallel circuit, if one bulb fuses, the other bulbs:

In a series circuit, if one bulb fuses, the other bulbs:

Which combination of resistors provides the lowest equivalent resistance?

An electric iron of 1000 W is used for 2 hours daily. If the cost of 1 unit of electricity is Rs. 5, what is the cost of using the iron for 30 days?

What is the equivalent resistance of three 6 Ohm resistors connected in parallel?

What is the total power consumed by two lamps rated 60W and 40W, respectively, when connected in parallel across a 220V supply?

The resistance of a wire is R. If it is stretched to twice its original length, its new resistance will be:

If the current through a resistor is doubled, the heat produced in a given time interval will:

A 2 Ohm resistor carries a current of 3 A. The heat produced in 10 seconds is:

Which of the following is an ohmic conductor?

If the temperature of a semiconductor increases, its resistance:

The direction of electron flow is ___________ to the conventional current.

The energy supplied by the cell in moving a unit charge from one end to the other is called its:

What is the cause of 'overloading' in domestic circuits?

What does a 'short circuit' mean in an electric circuit?

The symbol for a variable resistor is:

Why are copper wires generally used for electrical transmission?

If an electric bulb of 40W, 220V is connected to a 110V supply, the power consumed will be:

Which statement is true for voltage in a parallel circuit?

Which statement is true for current in a series circuit?

A device that changes the resistance in an electric circuit is called a:

The material of an electric fuse wire should have:

What is the effect of increasing temperature on the resistance of a pure metal conductor?

An electric cell converts:

Which of the following is true about electric potential?

The property of a conductor to resist the flow of current is called:

In a parallel circuit containing two resistors, if the current through the first resistor is 2 A and the total current is 5 A, what is the current through the second resistor?

A circuit consists of two resistors in series. If the voltage across the first resistor is 5 V and the total voltage is 12 V, what is the voltage across the second resistor?

If an electric bulb draws a current of 0.5 A when the voltage is 200 V, its power is:

If the reading of an ammeter is 2 A and the resistance is 10 Ohm, what is the voltage across the resistor?

A 60 W light bulb is switched on for 2 hours. How much electrical energy is consumed?

Which of the following represents electric power?

To increase the brightness of a bulb in a circuit, we can:

The resistance of an ideal voltmeter is:

The resistance of an ideal ammeter is:

Why is tungsten used for the filament of incandescent light bulbs?

Which material is typically used for heating elements in electric toasters and irons?

A component whose resistance changes with voltage is called a:

A current of 2 A flows through a conductor for 5 minutes. The amount of charge that passes through the conductor is:

The amount of current flowing through a circuit is 0.5 A. How much charge passes through a point in the circuit in 10 minutes?

If 100 J of work is done to move 4 C of charge from one point to another, the potential difference between the two points is:

What is the potential difference required to make 1 A of current flow through a resistance of 1 Ohm?

Which of the following is a good conductor of electricity?

The 'Ampere' is the unit of:

The unit 'Volt' is equivalent to:

An electric heater is rated 1500 W, 220 V. The current drawn by it is:

Two resistors of 10 Ohm and 20 Ohm are connected in parallel. The equivalent resistance is:

Two resistors of 10 Ohm and 20 Ohm are connected in series. The equivalent resistance is:

Resistivity of a conductor depends on:

The resistance of a conductor is inversely proportional to its:

How many electrons constitute one coulomb of charge?

What is the charge of an electron?

In an electric circuit, the conventional direction of current flow is:

A 220 V, 100 W bulb has a resistance of approximately:

Which of the following factors does not affect the resistance of a conductor?

When the cross-sectional area of a metallic wire is doubled, its resistance will:

When the length of a metallic wire is doubled, its resistance will:

If a wire of resistance R is cut into two equal halves, the resistance of each half will be:

Why are domestic electrical appliances usually connected in parallel?

The material used for the filament of an electric bulb is usually:

An electric fuse is used as a safety device in circuits to:

1 kilowatt-hour is equivalent to:

The commercial unit of electrical energy is:

The SI unit of electric power is:

The rate at which electrical energy is consumed or dissipated in an electric circuit is called:

Which of the following is an application of the heating effect of electric current?

The heating effect of electric current is given by:

When resistors are connected in parallel, the reciprocal of the total resistance is equal to:

When resistors are connected in series, the total resistance is:

Which of the following materials has the lowest electrical resistivity?

The SI unit of electrical resistance is:

The resistance of a conductor depends on:

According to Ohm's Law, if the potential difference across a conductor is doubled, the current flowing through it will:

Ohm's Law states the relationship between:

A device used to measure potential difference across two points in an electric circuit is called:

The SI unit of potential difference is:

The work done in moving a unit charge from one point to another in an electric circuit is called:

A device used to measure electric current in a circuit is called:

The SI unit of electric current is:

The flow of electric charge is known as:

Which of the following is an example of an electrical insulator?

The SI unit of electric charge is:

What determines the rate at which energy is delivered by a current?

An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.

Compute the heat generated while transferring 96000 coulomb of charge in one hour through a potential difference of 50 V

What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series?

Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?

Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?

Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?

On what factors does the resistance of a conductor depend?

What is meant by saying that the potential difference between two points is 1 V?

Name a device that helps to maintain a potential difference across a conductor.

Calculate the number of electrons constituting one coulomb of charge.

Define the unit of current.

What does an electric circuit mean?

How much energy is given to each coulomb of charge passing through a 6 V battery?

What is the maximum resistance which can be made using five resistors each of 1/5 Ω ?

A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross section of the filament in 16 seconds would be roughly.

Calculate the resistivity of the material of a wire of length 1 m, radius 0.01 cm and resistance 20 ohms.

List the factors on which the resistance of a conductor in the shape of a wire depends.

Why are alloys commonly used in electrical heating devices ?

Why are metals good conductors of electricity whereas glass is a bad conductor of electricity ? Give reason.

Calculate the resistance of a metal wire of length 2 meters and cross-sectional area 1.55 × 10⁻⁶ square meters, if the resistivity of the metal is 2.8 × 10⁻⁸ ohm meter.

How is the resistivity of alloys compared with those of pure metals from which they may have been formed?

Name a device that you can use to maintain a potential difference between the ends of a conductor. Explain the process by which this device does so.