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प्रश्न
What is overloading?
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उत्तर
When consumption of electrical power is huge, excessive current is drawn from the transformer supplying the electricity, and if the capacity of the transformer is insufficient, its fuse wire melts and the supply gets shutdown. Such events as called as overloading.
संबंधित प्रश्न
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
How does the resistance of a wire vary with its area of cross-section?
The safety device based on the heating effect of electric current is called a ______.
Why are the coils of electric irons and electric toasters made of an alloy rather than a pure metal?
How does the resistance of a wire vary with its:
diameter?
An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
A resistance of 25 Ω is connected to a 12 V battery. Calculate the heat energy in joules generated per minute.
What is meant by the heating effect of current? Give two applications of the heating effect of current.
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
Two exactly similar heating resistances are connected (i) in series, and (ii) in parallel, in two different circuits, one by one. If the same current is passed through both the combinations, is more heat obtained per minute when they are connected in series or when they are connected in parallel? Give reason for your answer.
Identify the figure and give its use.
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.
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.
Why does tungsten metal used to make solenoid type coil in an electric bulb?
In an electric bulb, coil of _______ metal is used.
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Define fuse.
Which of the following is correct?
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- Will the bulb in the two circuits glow with the same brightness? Justify your answer.
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Explain the working of an electric fuse.
Fuse is a strip of alloy wire which is made up of lead and tin with a very low ______.
Name a few appliances which work on the basis of the heating effect of current.
What is a trip switch?
An electrochemical cell converts ______ energy into ______ energy.
The electric fuse works on the Joule heating principle.
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1 kWh is equal to ______.
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| 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 which of the following applications of Iron, rusting will occur most? Support your answer with valid reason.
| A | B | C | D |
 |
 |
 |
 |
What is the heating effect of electric current?
State the law that explains the heating effect of current with respect to the measurable properties in an electrical circuit.
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
