Lighting Effect of Electric Current
Trending Questions
Two resistors A and B of resistance 4 ohm and 6 ohm respectively are connected in parallel. The combination is connected across a 6 volt battery of negligible resistance. Calculate: (i) the power supplied by the battery, and (ii) the power dissipated in each resistor.
You take two resistors of resistance 2 R and 3R and connect them in parallel in an electric circuit. Calculate the ratio of electric power consumed by 2 R and 3R.
At a given time a house is supplied with 100 A at 220 V. How many 75 W, 220 V light bulbs could be switched on in the house at the same time (if they are all connected in parallel)?
An electric bulb is rated 240 V- 60W and is working at 100% efficiency.
Calculate the resistance of the bulb.
Two bulbs A and B are marked as ‘A’ 60W, 220V & ‘B’ 100W, 220V are connected in parallel to 220 V source. Which of the two will glow brighter?
Bulb B
Same brightness
‘A’ glows but ‘B’ does not
Bulb A
An electric bulb rated 220 V, 60 W is working at full efficiency.
Another identical bulb is connected in series with the first one and the system is connected across the mains as shown in the diagram:
The total power of the bulbs is:
60 W
120 W
15 W
30 W
In an electrical circuit three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness?
(a) Brightness of all the bulbs will be the same
(b) Brightness of bulb A will be the maximum
(c) Brightness of bulb B will be more than that of A
(d) Brightness of bulb C will be less than that of B
Statement 1: It is observed that sometimes an incandescent bulb glows brighter and sometimes it glows dim.
Statement 2: Glowing brighter and dimmer depends on heating effect of current. More current produces more heating effect making the bulb glow brighter and vice-versa.
Both the statements are true and statement 2 is the correct explanation of statement 1.
Both the statements are true but statement 2 is not the correct explanation of statement 1.
Statement 1 is correct and statement 2 is false.
Statement 1 is false and statement 2 is correct.
By connecting an extra appliance in parallel to the initial appliance for the constant input power, we
increase the power output
keep the output power constant
make the power output zero
reduce output power compared to that of input power
A motor that pumps up water to a tank requires 10kW power. Its operating voltage is 220V. The only available resistor has a resistance of 11Ω. We know that we must use n such resistors in series and p such series resistor combinations in parallel. The values of n and p are respectively
In an electrical circuit three incandescent bulbs A, B and C of rating 40 W, 60 W and 100 W respectively are connected in parallel to an electric source. Which of the following is likely to happen regarding their brightness?
(a) Brightness of all the bulbs will be the same
(b) Brightness of bulb A will be the maximum
(c) Brightness of bulb B will be more than that of A
(d) Brightness of bulb C will be less than that of B
The filament of a bulb glows due to?
Chemical effect of electric current.
All of these.
Heating effect of the electric current.
Magnetic effect of electric current.
- Brightness of all the bulbs will be the same
- Brightness of bulb A will be the maximum
- Brightness of bulb B will be more than that of A
- Brightness of bulb C will be less than that of B
