English

In a House Two 60 W Electric Bulbs Are Lighted for 4 Hours, and Three 100 W Bulbs for 5 Hours Everyday. Calculate the Electric Consumed in 30 Days. - Science

Advertisements
Advertisements

Question

In a house two 60 W electric bulbs are lighted for 4 hours, and three 100 W bulbs for 5 hours everyday. Calculate the electric consumed in 30 days.

Advertisements

Solution

Power of bulb 1, P1 = 60 W
Duration that it was lit, t1= 4 h
Electric energy consumed by two bulbs, E1 = 2 x P1 x t1
                                                                     = 2 x 60 x 4
                                                                     = 480 Wh

Power of bulb 2, P2 = 100 W
Duration that it was lit, t2= 5 h
Electric energy consumed by three bulbs, E2= 3 x P2t2 = 3 x 100 x 5 = 1500 Wh

Total electric energy consumed in 30 days, E = 30 x (E1E2)
                                                                     E = 30 x (480 + 1500)
                                                                     E = 30 x 1980                                                      
                                                                     E = 59400 Wh
                                                                     E = 59.4 kWh

shaalaa.com
  Is there an error in this question or solution?
Chapter 1: Electricity - Exercise 7

APPEARS IN

Lakhmir Singh Physics (Science) [English] Class 10
Chapter 1 Electricity
Exercise 7 | Q 18

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

1 kWh = ________ J


If a bulb of 60W is connected across a source of 220V, find the current drawn by it.


Name two safety devices which are connected to the live wire of a household electric circuit


Which one has a higher electrical resistance : a 100 watt bulb or a 60 watt bulb?


An electric heater of resistance 8 Ω takes a current of 15 A from the mains supply line. Calculate the rate at which heat is developed in the heater. 

 


Electrical power P is given by the expression P = (Q × V) ÷ time. What do the symbols Q and V represent?


 State and define the household unit of electricity.


An electrical appliance having a resistance of 200Ω is operated at 200 V. Calculate the energy consumed by the appliance in 5 minutes (i) in joules (ii) in kWh.


An electric toaster draws 8 A current in a 220 V circuit. It is used for 2 h. Find the cost of
operating the toaster if the cost of electrical energy is Rs. 4.50 per kWh.


An electric bulb marked 220 V, 100 W will get fused if it is made to consume 150 W or more. What voltage fluctuation will the bulb withstand?


In a house two 60 W electric bulbs are lighted for 4 hours, and three 100 W bulbs for 5 hours every day. How much is the electric energy consumed during the month of June?

Express watt hour and kilowatt hour in joule.


What are the two main systems of wiring commonly used in houses? Which of these systems mentioned by you is better and why?


An electric heater is rated 220 V, 550 W. Electrical energy is also measured in kWh. What do you understand by a kilo-watt-hour?


State the reason why, in a three pin plug, the earth pin is longer and thicker than the other two.


At what voltage is the electric power generated at the generating station? Explain the transmission of this power to your house.


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. 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 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:


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×