Advertisements
Advertisements
प्रश्न
What is the meaning of electric power of an electrical device? Write its SI unit.
Advertisements
उत्तर
Electric power is the measure of the rate of electrical energy transfer by an electric circuit per unit time.
P = `"E"/"t"`
Its SI unit is the watt (W).
APPEARS IN
संबंधित प्रश्न
An electric motor takes 5 amperes current form a 220 volt supply line. Calculate the power of the motor and electric energy consumed by it in 2 hours.
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.
1kWh = …….. J
What are the two main systems of wiring commonly used in houses? Which of these systems mentioned by you is better and why?
What changes in energy occur in an electric heater?
Establish the relation that heat produced in a metallic conductor due to the flow of current is V2t/R joules, where V is the potential difference across the ends of the conductor, R its resistance and t is the time in second for which current flows.
Two bulbs are rated: bulb A 100W, 120 V bulb B 10W, 120 V. If both are connected across a 120V supply, which bulb will consume more energy, When in series? Also calculate the current through each bulb in above cases.
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:
What is the commercial unit of electrical energy? Represent it in terms of joules.
The average work done by a human heart while it beats once is 0.5 Joule. The power used by heart if it beats 72 times in a minute:
