Advertisements
Advertisements
प्रश्न
A bulb is rated as 250 V; 0.4 A. Find its : (i) power, and (ii) resistance.
Advertisements
उत्तर
Given:
V = 250 V
I = 0.4 A
Power, P = VI
= 250 x 0.4
= 100 W
Resistance, R = `R=P/(I2) `
= `100/(0.4)^2`
= 625 Ω
APPEARS IN
संबंधित प्रश्न
Which particles are responsible for current in conductors?
An electric kettle connected to the 230 V mains supply draws a current of 10 A. Calculate:
(a) the power of the kettle.
(b) the energy transferred in 1 minute.
An electric fan runs from the 230 V mains. The current flowing through it is 0.4 A. At what rate is electrical energy transferred by the fan?
When an electric lamp is connected to 12 V battery, it draws a current of 0.5 A. The power of the lamp is:
(a) 0.5 W
(b) 6 W
(c) 12 W
(d) 24 W
Which of the following is likely to be the correct wattage for an electric iron used in our homes?
(a) 60 W
(b) 250 W
(c) 850 W
(d) 2000 W
What is the current I in the given circuit (Fig. )?
A simple electric circuit has a 30 V battery and a resistor ot 60 o. What will be the current in the circuit? The resistance of the oonnecting wires is negligible.
Express watt hour and kilowatt hour in joule.
What is the order of current drawn by appliances connected to the ‘light circuit’ of a household?
What is the function of the split rings in a d.c. motor?
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the resistance of each heater.
An electric kettle is rated 3kW, 250V. What should be the current capacity of the fuse with it?
A. bulb is rated at 100W, 250V and another one at 60W, 250V. What is the current flowing in the circuit if the two bulbs are put in series across a 220 V mains supply?
The resistance of filament of an electric heater is 500 Ω It is operated at 200V for 1 hour daily. Calculate the current drawn by the heater and the energy consumed in kWh, by the heater in a month of 30 days.
A torch bulb is rated at 3 V and 600 mA. Calculate it’s
- power
- resistance
- energy consumed if it is used for 4 hours.
A cooler of 1500 W, 200 volts and a fan of 500 W, 200 volts are to be used from a household supply. The rating of fuse to be used is:
1 mV is equal to:
A family uses 8 kW of power. Direct solar energy is incident on the horizontal surface at an average rate of 200 W per square meter. If 20% of this energy can be converted to useful electrical energy, how large an area is needed to supply 8 kW?
A electric bulb is rate 220 V, 60 W. its electric cell resistance is nearly
What is the meaning of electric power of an electrical device? Write its SI unit.
