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प्रश्न
Find the odd one out.
पर्याय
Heater
Toaster
Electric bulb
Electric iron
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उत्तर
Electric bulb
Explanation:
Electric bulbs use tungsten filaments, but others have nichrome filaments.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
The safety device based on the heating effect of electric current is called a ______.
What is nichrome? State its one use.
Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
A heating coil has a resistance of 200 Ω. At what rate will heat be produced in it when a current of 2.5 A flows through it?
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
The heat produced by passing an electric current through a fixed resistor is proportional to the square of:
(a) magnitude of resistance of the resistor
(b) temperature of the resistor
(c) magnitude of current
(d) time for which current is passed
The current passing through an electric kettle has been doubled. The heat produced will become:
(a) half
(b) double
(c) four time
(d) one-fourth
An electric fuse works on the:
(a) chemical effect of current
(b) magnetic effect of current
(c) lighting effect of current
(d) heating effect of current
Give Scientific reason
In the electric equipment producing heat e.g. iron, electric heater, boiler, toaster etc, an alloy such as Nichrome is used, not pure metals.
Identify the figure and give its use.
An electric iron of 1100 W is operated for 2 hrs daily. What will be the electrical consumption expenses for that in the month of April? (The electric company charges Rs 5 per unit of energy).
Statement 1 : Electric current ( flow of electrons ) creates heat in the resistor.
Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
The ‘live’ and the ‘neutral’ wires have potential difference of _______.
What is a short circuit?
Write two devices based on the heating effect of electric current.
Write scientific reason.
A coil made up of alloy Nichrome is used in the electric heater cooker as a resistor.
Name any two appliances which works on the phenomenon of heating effect of electric current.
What does overloading cause?
Name any two appliances which work under the principle of heating effect of current.
Which of the following is correct?
A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of:
Which of the following gases are filled in electric bulbs?
What is Joule’s heating effect? How can it be demonstrated experimentally? List its four applications in daily life.
When a switch is in OFF position,
- circuit starting from the positive terminal of the cell stops at the switch.
- circuit is open.
- no current flows through it.
- current flows after some time.
Choose the combination of correct answer from the following.
An MCB can be used instead of a fuse in an electrical circuit.
An electric fuse has a body made of ceramic and two points for connecting the fuse wire.
It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.
______ wire is used in the filament of the bulbs.
A student boils water in an electric kettle for 20 minutes. Using the same mains supply he wants to reduce the boiling time of water. To do so should he increase or decrease the length of the heating element? Justify your answer.
An electric fuse is a wire made up of a material having ______ melting point.
The electric fuse works on the Joule heating principle.
If 220 V potential difference is applied across an electric bulb, a current of 0.45 A flows in the bulb. What must be the power of the bulb?
Two students decided to investigate the effect of water and air on iron object under identical experimental conditions. They measured the mass of each object before placing it partially immersed in 10 ml of water. After a few days, the object were removed, dried and their masses were measured. The table shows their results.
| Student | Object | Mass of Object before Rusting in g |
Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
What might be the reason for the varied observations of the two students?
What is the heating effect of electric current?
When a current I flows through a wire of resistance R for time t then the electrical energy produced is given by ______.
An electric iron is rated 220 V, 2 kW. If the iron is used for 3h daily find the cost of running it for one week if it costs ₹ 4.25 per kWh.
