Advertisements
Advertisements
At what voltage is the electric power generated at the generating station? Explain the transmission of this power to your house.
Concept: undefined >> undefined
How is the amount of heat produced calculated due to the passage of current in a metallic conductor? Derive an expression for it.
Concept: undefined >> undefined
Advertisements
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate total current taken from the supply.
Concept: undefined >> undefined
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the resistance of each heater.
Concept: undefined >> undefined
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the energy supply in kWh to the three heaters in 5 hour.
Concept: undefined >> undefined
An electric bulb is rated 240V-60W and is working at 100% efficiency.
(i) Calculate the resistance of bulb.
(ii) (a) Draw the circuit diagram.
(b) What is the rate of conversion of energy in each bulb?
(c) Total power used by the bulbs.
Concept: undefined >> undefined
With reference to the diagram shown below calculate:

(i) The equivalent resistance between P and Q.
(ii) The reading of ammeter.
(iii) The electrical power between P and Q.
Concept: undefined >> undefined
State other bigger units of electric power and express them in watt.
Concept: undefined >> undefined
State (i) the S. I. unit, (ii) the household unit, of electrical energy. How are these units related?
Concept: undefined >> undefined
An electric kettle is rated 3kW, 250V. What should be the current capacity of the fuse with it?
Concept: undefined >> undefined
I ampere of current is passed through a resistor of resistance R ohm for time t second. Obtain expression for
(i) the electrical energy, and
(ii) the electrical power spent.
Concept: undefined >> undefined
How can electric energy consumed by an electric appliance be calculated in kilowatt hour (kWh)?
Concept: undefined >> undefined
What is the resistance of an appliance rated at V volt, P watt?
Concept: undefined >> undefined
A family uses a light bulb of 100W, a fan of 100W, and a heater of 1000W, each for 8 hours a day. If the cost of electricity is Rs. 2 per unit, what is the expenditure to the family per day, on electricity?
Concept: undefined >> undefined
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.
Concept: undefined >> undefined
Find the heat produced in joules when a current of 10 amperes flows through a connecting wire of resistance 2 × 10-2 ohms and heating element of resistance 250 ohms for 2 seconds.
Concept: undefined >> undefined
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?
Concept: undefined >> undefined
Find the energy released by a current of 0.25 amperes flowing through a heater for 5 minutes. The p.d. is 230 V.
Concept: undefined >> undefined
An electric iron is rated at 230 V, 750 W. What is its resistance? What maximum current can be passed through it?
Concept: undefined >> undefined
An electric bulb is rated as 100W – 250V. What information does it convey? Calculate the resistance of its filament while glowing.
Concept: undefined >> undefined
