Q. A blacksmith heats a 1.9kg iron horseshoe to 480 degree C, then plunges it into a bucket containing 10kg of water at 20 degree C. The specific heat of iron is 447J/kgK.What is the final temperature?
Q. A silicon monoxide (n = 1.45) film of 100 nm thickness is used to coat a glass camera lens (n = 1.56). What wavelength of light in the visible region (390 to 710 nm) will be most efficiently transmitted by this system? (1 nm = 10-9 m)