How can you tell that this iron operates using the mains supply?

[chessie273]

Hi, I'm new to the forum so i don't really quite know what I'm doing yet!

anyway, i know this question is REALLY basic but physics is not my forte and I'm confused...

"John has just bought a new iron and sees this plate on the handle -
230V
1840W
50Hz"

John irons a shirt for 10s

energy transformed = power x time

so if I'm correct:
time = 10s
power= 1840W
energy transformed = 18400J

the final question "John can tell from the plate that the iron can operate using mains supply. How can he tell this?"

and i have absolutely no idea!

help would be greatly appreciated - i really need to understand this, its from a gcse mock paper and my exam is in a couple of weeks!

 

[chroot]

I don't actually see any question. Where did the 10 seconds come from?

You should post the question exactly as it was given to you.

- Warren