Sunday, February 12, 2012

Calculate the cost of using a hair dryer?

the cost of one unit of electricity is 8p

the hair dryer uses 1800 watts

the sheet says total cost = number of kilowatts hours x cost per killowatt hour

do not work out just tell me what i should do

so then i learn something out of thisCalculate the cost of using a hair dryer?
You're missing one critical piece of information: how long is the hair dryer being used?



Electric usage is measured in kilowatt-hours.

1 kilowatt-hour is the equivalent of 1000 watts for 1 hour.



Three values are needed to calculate the cost to use an appliance:



The power rating or wattage of the appliance. This is found on the appliance e.g. 50W or 1800W.



The time the appliance is switched on in hours (or minutes 梅 60)



The cost per KWh.



1. Appliance wattage 梅 1000 = kilowatts (kW)

In your problem, we know this is 0.18 (1800 / 1000)



2. Kilowatts 脳 (time appliance is switched on in hours) = kilowatt hours (kWh)

We don't know the time the appliance is switched on; call it h (in hours). So kilowatt hours = 0.18*h



3. Kilowatt hours x cost per KWh is what you pay for that appliance to run.

Your problem says the cost of one unit of electricity is 8p - is that the cost per kilowatt hour?



If so, then your total cost is 0.18*h*8p or (1.44*h)p. So running the hair dryer for an hour would cost 1.44pCalculate the cost of using a hair dryer?
1 dollar and 2 seconds

No comments:

Post a Comment