Advertisements
Advertisements
Question
The electric bulbs used these days have a coil-coiled filament. State its reason.
Solution
On account of having a coil-coiled filament, the area of spread of tungsten is much and so the heat now produced in a very small area, raises the temperatures to a high degree i.e., 2300°C, producting more bright light.
APPEARS IN
RELATED QUESTIONS
What is consumed using different electrical appliances, for which electricity bills are paid?
Which uses more energy : a 250 W TV set in 1 hour or a 1200 W toaster in 10 minutes?
An electric heater of resistance 8 Ω takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater.
Which of the following is the most likely temperature of the filament of an electric light bulb when it is working on the normal 220 V supply line?
(a) 500°C
(b) 1500°C
(c) 2500°C
(d) 4500°C
What is the current I in the given circuit (Fig. )?
Name three main characteristics of an heating element.
An electric lamp A of 40 W and another electric lamp B of 100 W are connected to 220 V supply. Calculate the ratio of their filament resistances?
A bulb is connected to a battery of e.m.f. 6V and internal resistance 2Ω A steady current of 0.5A flows through the bulb. Calculate the total energy supplied by the battery in 10 minutes.
An immersion rod having resistance of 50 Ω is connected to 220V main supply. Assuming that all the energy generated goes to heat the water, calculate the time taken to heat 5 kg water from 30°C to 100°C.
Electric power is inversely proportional to ____________.
