Thursday, April 26, 2012

If a hair dryer uses 1.721 x 10 kcal in 1.000 mins, how many watts does it use?

I need a detailed answer with calculations and and explanation.



If a hair dryer uses 1.721 x 10 kcal in 1.000 mins, how many watts does it use?

Watts is power, KCals is energy. You have to convert Kcals to watt-hours, using the conversion 1 KCal = 1.163 watt-hour. 1.721 x 10 = 17.21 x 1.163 = 20.015, call it 20, watt-hours. It takes 1000 minutes to consume them. That's 16 and two thirds hours (divide by 60). 20 over 16.666666 = 1.2 watts, which is implausibly low for a hairdryer (1200 watts is more probable), so you may want to check that the decimal point in 1.721 is not meant to be a comma, unless the whole hairdryer story is just a red herring.



If a hair dryer uses 1.721 x 10 kcal in 1.000 mins, how many watts does it use?

Hay .. What are u using ???17.21 Kcal of what u r using??



How many watts does "it " use ?? HEre What is " IT"



u didn't specify the Noun then Hoow can u use a prounoun..



Don;'t think that everyone dry the hair...Or give some additional information to answer....Sorry If i do anything wrong



Your question is not specific..



If a hair dryer uses 1.721 x 10 kcal in 1.000 mins, how many watts does it use?

A standard high power 1'200W hair dryer would use 17'225 kcal in 1'000 minutes.



The figure you give is "1.721x10", looks like a power of 10 is missing. If I assume it is the 4th power, i.e. 1.721E4, then you have:



kilocalories in 1'000 minutes: 1.721E4



calories in 1'000 minutes: 1.721E7 (1'000 calories to a kilocalorie)



calories per second: 2.868E2 (divide by 1'000 times 60 i.e. 60'000)



Joules per second: 1.199E3 (multiply by 4.18, there are 4.18 Joules to a calorie)



A Joule per second is also called a Watt.



So your hairdryer use up a power of 1'199 Watt, let's say 1'200 in round numbers. That's as much as 12 high-power lightbulbs.



If a hair dryer uses 1.721 x 10 kcal in 1.000 mins, how many watts does it use?

Energy = 1.721 x 10 Kcal



= 17210 cal



= 71937.8 Joules



Time = 1 minute



= 60 seconds



Power = Energy/time



= 71937.8/60



= 1198.963 watts.



= 1200 watts (approximately)

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