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प्रश्न
How can overloading be avoided?
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उत्तर
Overloading in the electric circuit can be avoided by not connecting many electric appliances at a time in the circuit.
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संबंधित प्रश्न
State four most common electrical appliances based on heating effect of electric current. Why do we use finely heated platinum wire in surgery?
The safety device based on the heating effect of electric current is called a ______.
Write Joule's law of heating.
An electric heater is connected to the 230 V mains supply. A current of 8 A flows through the heater.
- How much charge flows around the circuit each second?
- How much energy is transferred to the heater each second?
An electric kettle rated at 220 V, 2.2 kW, works for 3 hours. Find the energy consumed and the current drawn.
Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.
Explain why, tungsten is used for making the filaments of electric bulbs.
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
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
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:
Give Scientific reasons.
In the electric equipment producing heat e.g. iron, electric heater, boiler, toaster etc, an alloy such as Nichrome is used, not pure metals.
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.
Which of the following substance contracts on heating?
What is the heating effect of electric current?
What is used to turn off the sudden increase in current in the electrical circuit of the house nowadays?
Which of the following is correct?
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:
Which of the following gases are filled in electric bulbs?
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?
B1, B2 and B3 are three identical bulbs connected as shown in Figure. When all the three bulbs glow, a current of 3A is recorded by the ammeter A.
- What happens to the glow of the other two bulbs when the bulb B1 gets fused?
- What happens to the reading of A1, A2, A3 and A when the bulb B2 gets fused?
- How much power is dissipated in the circuit when all the three bulbs glow together?
(a) Observe the diagram given below and state whether the bulb will glow or not when we switch on K.
(b) Is it safe to handle the bulb when the switch is OFF?
(c) Give a reason for your answer in (b).
An electric cell produces electricity from the ______ ______ in it.
Name two electric devices for each where
- heating effect of current is used and
- magnetic effect of current is used.
Paheli took a wire of length 10 cm. Boojho took a wire of 5 cm of the same material and thickness. Both of them connected the wires as shown in the circuit given in the following figure. The current flowing in both the circuits is the same.
- Will the heat produced in both cases be equal? Explain.
- Will the heat produced be the same if the wires taken by them are of equal lengths but of different thickness? Explain.
An electric fuse has a body made of ceramic and two points for connecting the fuse wire.
What is an electric fuse made up of?
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.
An electric fuse is a wire made up of a material having ______ melting point.
The electric fuse works on the Joule heating principle.
Explain why fuse wire is always connected in a series arrangement.
What is the heating effect of electric current?
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.
