Physics

Need help with this question, why? because a wasp was flying around and i got too scared to concentrate... MUCH APPRECIATED FOR HELP :smile:

A new house is fitted with all the latest energy efficiency measures. An energy surveyor checks a new house and finds that each second a house is losing 125W of heat through it’s roof. The heaters in the house are producing around 800W of heat. How efficient are energy efficient measures?

Reply 1

RDKGames

Study Forum Helper

Key word there is "was" so now it's gone. You may concentrate. Good luck.

Reply 2

cpaige21

As in, a percentage?

Posted from TSR Mobile

Reply 3

Carthaginian

Dude you're like 50 times bigger than a wasp, why be scared of it?

Reply 4

DarkEnergy

Original post by Xander25

Need help with this question, why? because a wasp was flying around and i got too scared to concentrate... MUCH APPRECIATED FOR HELP :smile:

((EnergyInput - WastedEnergyOutput)/EnergyInput)*100
Might be wrong, haven't done efficiency in a while.

Reply 5

username2752874

Original post by DarkEnergy

((EnergyInput - WastedEnergyOutput)/EnergyInput)*100
Might be wrong, haven't done efficiency in a while.

You're right; surely by your username you're studying A Level Physics?

Reply 6

Starlight2000

Original post by Xander25

Need help with this question, why? because a wasp was flying around and i got too scared to concentrate... MUCH APPRECIATED FOR HELP :smile:

Forget that it is losing that much every second
Use this : (useful energy output/useful energy input) then multiply by 100
Apparently my year were the last to be provided with a formulae sheet in the exam so you'll have to learn all of them off by heart. This is quite easy so just get it in your head. Also notice I haven't given you the answer but I hope giving you the formula has cleared things up for you :smile:

Reply 7

DarkEnergy

Original post by GradeA*UnderA

You're right; surely by your username you're studying A Level Physics?

Good observation :smile:

Just a bit rusty on the basics atm, efficiency was in AS but I've pretty much forgotten all of AS over the summer & the question seems a bit weirdly worded.