Advertisements
Advertisements
Question
Which of the following characteristic is not suitable for a fuse wire?
(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring
Advertisements
Solution
thick and short
This is so because in this case, the resistance of the wire will be low.
APPEARS IN
RELATED QUESTIONS
Why is the tungsten used almost exclusively for filament of electric lamps?
Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
When current is switched ‘on’ in a room heater, it ______.
Write Joule's law of heating.
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.
Answer the following question:
what is the heating effect of the electric current? state any four applications of it?
The electricity bill specifies the usage in _______.
How can overloading be avoided?
Define fuse.
How does use of a fuse wire protect electrical appliances?
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?
An electric component used as a safety device is electric circuit is ______.
An MCB can be used instead of a fuse in an electrical circuit.
It would cost a man Rs. 3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board.
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?
Write an expression for the amount of heat produced in a resistor when an electric current is passed through it stating the meanings of the symbols used.
An electric iron of resistance 20 Ω draws a current of 5 A. The heat developed in the iron in 30 seconds is ______.
