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प्रश्न
The electricity bill specifies the usage in _______.
विकल्प
kilowatt
joule
volt
unit
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उत्तर
The electricity bill specifies the usage in unit.
APPEARS IN
संबंधित प्रश्न
An electric iron of resistance 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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.
When current is switched ‘on’ in a room heater, it ______.
The safety device based on the heating effect of electric current is called a ______.
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?
How does the resistance of a wire vary with its:
diameter?
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, the current that makes the heater element very hot, only slightly warms the connecting wires leading to the heater.
Derive the expression for the heat produced due to a current 'I' flowing for a time interval 't' through a resistor 'R' having a potential difference 'V' across its ends. With which name is this relation known?
What is meant by the heating effect of current? Give two applications of the heating effect of current.
If the current flowing through a fixed resistor is halved, the heat produced in it will become:
Which electric heating device in your home do you think have resistors which control the flow of electricity?
Give a scientific reason.
Tungsten metal is used to make a solenoid type coil in an electric bulb.
Give Scientific reason.
In practice, the unit kWh is used for the measurement of electrical energy, rather than joule.
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?
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.
Write the mathematical expression for Joule’s law of heating.
In an electric bulb, coil of _______ metal is used.
A coil of an alloy _______ is used in electric heater cooker as a resistor.
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.
Define fuse.
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:
An electric bulb is connected to a 220 V generator. The current is 0.50 A. What is the power of the bulb?
Which of the following gases are filled in electric bulbs?
Assertion: Bending of wire decreases the resistance of the electric wire.
Reason: The resistance of a conductor depends on length, thickness, nature of material and temperature of the conductor.
An electric component used as a safety device is electric circuit is ______.
An electric cell produces electricity from the ______ ______ in it.
An MCB can be used instead of a fuse in an electrical circuit.
Fuse is a strip of alloy wire which is made up of lead and tin with a very low ______.
An electric fuse is a wire made up of a material having ______ melting point.
Explain why fuse wire is always connected in a series arrangement.
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?
