1. The problem statement, all variables and given/known data 1)Wally whacko claims to have invented a heat engine that will revulutionalise the industry. It runs between a hot source at 300 C and a cold sink at 25 C . he claims that his engine is 92 % effieicnt. What is the max efficiency of his engine ? in 2sf (2)At a certain location the solar power per unit area reaching earth suface is 200 w/m^2. Averaged over 24 hour day. If the average requirement in your home is 3.8 kw and you can convert solar power to elevtric power with 10% efficiency, how large a collector area will you need to meet all your house hold energy requirement from solar energy. (3)The soecific heat capacity of ice is about 0.5 cal/g C. Suppose that it remains at that value all the way to absolute zero. Calculate the number of calories it would take to change a 0.90g ice cube at absolute zero ( -273 C) t 0.90 g of boiling water. How does this number of calories compare with the number of calories required to change the same gram of 100 C boiling water to 100 C steam. ? 2. Relevant equations 1) t(h)-t(c)/ t(h) i dont know number 2 3) q=mct 3. The attempt at a solution 1) 300-25 /300 = 91.667 so its 91.667% efficeint 2) idont know where to start 3) o.90 x -273 x 0.5= -122.850 are they right ? please correct me if i am wrong with proper working thanks !