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प्रश्न
What does overloading cause?
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उत्तर
Due to overloading, fuse wire melts and the supply gets shut down.
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संबंधित प्रश्न
Why is the tungsten used almost exclusively for filament of electric lamps?
When current is switched ‘on’ in a room heater, it ______.
What is nichrome? State its one use.
An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
Name the material which is used for making the filaments of an electric bulb.
The heat produced in a wire of resistance 'x' when a current 'y' flows through it in time 'z' is given by:
(a) x2 × y × z
(b) x × z × y2
(c) y × z2 × x
(d) y × z × x
If the current flowing through a fixed resistor is halved, the heat produced in it will become:
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?
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For electric power transmission, copper or aluminium wire is used.
Give Scientific reason.
In practice, the unit kWh is used for the measurement of electrical energy, rather than joule.
Identify the figure and give its use.
Solve the following example.
Two tungsten bulbs of wattage 100 W and 60 W power work on 220 V potential difference. If they are connected in parallel, how much current will flow in the main conductor?
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.
Rewrite the following statement by selecting the correct option:
1 A = ____________ mA.
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what is the heating effect of the electric current? state any four applications of it?
What is overloading?
Write two devices based on the heating effect of electric current.
When does overloading occur?
Name some devices that run using heat effect of electric current
Heating effect of current is called ______
Name any two appliances which work under the principle of heating effect of current.
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Name two electric devices for each where
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What are the uses of electromagnets?
Explain the working of an electric fuse.
Name a few appliances which work on the basis of the heating effect of current.
What is a trip switch?
A trip switch is a ______ safety device.
Find the odd one out.
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?
In a set up the students coated iron nails with zinc metal and noted that, iron nails coated with zinc prevents rusting. They also observed that zinc initially acts as a physical barrier, but an extra advantage of using zinc is that it continues to prevent rusting even if the layer of zinc is damaged. Name this process of rust prevention and give any two other methods to prevent rusting.
What is the heating effect of electric current?
Anannya responded to the question: Why do electrical appliances with metallic bodies are connected to the mains through a three-pin plug, whereas an electric bulb can be connected with a two-pin plug?
She wrote: Three-pin connections reduce heating of connecting wires.
- Is her answer correct or incorrect? Justify.
- What is the function of a fuse in a domestic circuit?
