PHYSIS HELP: why do vegies cook faster when steamed rather then boiled?

Question

could someone explain the science behind it

Answer 1

water cannot be above 100 degrees centigrade, so there is a max on how hot it can get, but there isn't a limit to how how steam can get, so the veggies cook faster.

Edit: water cannot be above 100 centigrade because then it'll turn into steam, just to be very, very clear

Answer 2

When you boil water hotter and hotter it eventually becomes steam, steam is therefore at a higher temperature than boiling water. So, steam will heat things to a higher temperature than boiling water :) Think of it as a reverse of water freezing.

Answer 3

Yes.  Steam is hotter, thus cooking the vegetables faster.  Boiling water will not get hotter than 212 F (water boils at 212 F at sea level.  In Denver, Colorado, it boils at about 202 F).  

This is because the atmospheric pressure is greater at sea level than it is at higher elevations.  A pressure cooker will allow water to boil at a higher temp.  Water boils at 257 F in a pressure cooker.