Advertisements
Advertisements
प्रश्न
An electric bulb is rated '100 W, 250 V'. How much current will the bulb draw if connected to a 250 V supply?
Advertisements
उत्तर
Given,
Power P = 100 W
Voltage V = 250 V
As Power, P = VI
I = `100/250`
= 0.4 A
APPEARS IN
संबंधित प्रश्न
Why are metals good conductors of electricity whereas glass is a bad conductor of electricity? Give reason?
One coulomb charge is equivalent to the charge contained in:
(a) 2.6 × 1019 electrons
(b) 6.2 × 1019 electrons
(c) 2.65 × 1018 electrons
(d) 6.25 × 1018 electrons
For a heater rated at 4 kW and 220 V, calculate:
(a) the current,
(b) the resistance of the heater,
(c) the energy consumed in 2 hours, and
(d) the cost if 1 kWh is priced at Rs 4.60.
Complete the following sentence:
A fuse is a short piece of wire of high ......... and low
A 3 pin mains plug is fitted to the lead for a 1 kW electric kettle to be used on a 250 V A.C. supply. Which of the following statements is NOT correct?
(a) A 13 A fuse is the most appropriate value to use.
(b) The brown wire should be connected to the live side of the mains.
What is the function of a step-up transformer?
A bulb of 40 W is used for 12.5 h each day for 30 days. Calculate the electrical energy consumed.
Answer the following question.
An electric lamp of resistance 20 Ω and a conductor of resistance 4 0 are connected to a 6 V battery as shown in the circuit. Calculate: 
(a) the total resistance of the circuit,
(b) the current through the circuit,
(c) the potential difference across the (i) electric lamp and (ii) conductor, and
(d) power of the lamp.
Water : pipe :: Electric current : ______.
When an electric current is passed, electrons move from:
