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प्रश्न
State four most common electrical appliances based on heating effect of electric current. Why do we use finely heated platinum wire in surgery?
उत्तर
The four most common appliances based on the heating effect of electrical current are electric iron, electric heater, electric oven and electric toaster. Finely heated platinum wire is used in surgery for cutting tissues much more efficiently than a knife.
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संबंधित प्रश्न
An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
Write Joule's law of heating.
An electric room heater draws a current of 2.4 A from the 120 V supply line. What current will this room heater draw when connected to 240 V supply line?
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.
Why does the connecting cord of an electric heater not glow hot while the heating element does?
An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
The current passing through a room heater has been halved. What will happen to the heat produced by it?
Name the material which is used for making the filaments of an electric bulb.
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
How does the wire in the filament of a light bulb behave differently to the other wires in the circuit when the current flows?
What property of the filament wire accounts for this difference?
Which electric heating device in your home do you think have resistors which control the flow of electricity?
Name the factors on which the heat produced in a wire depends when current is passed in it, and state how does it depend on the factors stated by you.
Name any six domestic appliances based on the heating effect of electric current.
The ‘live’ and the ‘neutral’ wires have potential difference of _______.
These days when current in the circuit suddenly increases _______ switches are used.
Find the odd one out and give its explanation.
Write two devices based on the heating effect of electric current.
Explain the importance/uses of fuse wire.
How can overloading be avoided?
True or False – If False give the correct answer
The fuse wire does not melts whenever there is overload in the wiring.
Name some devices that run using heat effect of electric current
Name any two appliances which work under the principle of heating effect of current.
An electric iron draws a current of 4 A when connected to 220 V mains. Its resistance must be:
A fuse wire repeatedly gets burnt when used with a good heater. It is advised to use a fuse wire of:
An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
Three incandescent bulbs of 100 W each are connected in series in an electric circuit. In another circuit another set of three bulbs of the same wattage are connected in parallel to the same source.
- Will the bulb in the two circuits glow with the same brightness? Justify your answer.
- Now let one bulb in both the circuits get fused. Will the rest of the bulbs continue to glow in each circuit? Give reason.
An electric component used as a safety device is electric circuit is ______.
Can we use the same fuse in a geyser and a television set? Explain.
Match the following
| 1. | Bulb | a. | Conductor |
| 2. | Electroplating | b. |
Insulator |
| 3. | Pure water | c. | Heating effect of current |
| 4. | Salt solution | d. | Chemical effect of current |
Assertion: A current-carrying wire should be charged.
Reason: The current in a wire is due to the flow of free electrons in a definite direction.
Name the effect of the current responsible for the glow of the bulb in an electrical circuit.
What is a trip switch?
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?
Find the odd one out.
