Peter knocks a book off the 0.9 m-high table and it falls to the floor. Karin picks it up and places it back on the table. What is the total change in the gravitational potential energy of the book?
A. *delta*Ug = 0 J
B. *delta*Ug = 2 |mg| (0.9 m)
C. *delta*Ug = -mv 2

Cin carbonh in hydrogeno in oxygen

If the heat engine is a perfect carnot cycle engine, thenefficiency = (t2-t1)/t2   where t1=temperature of cold reservoir ( ° k) = 135            t2=temperature of hot reservoir ( ° k)   = 325thereforeefficiency = (t2-t1)/t2 = (325-135)/325 = 0.5846 = 58%  note: this is the theoretical maximum efficiency of a perfect heat engine.   real-life engines do not achieve this value.

Well it depends on the object or substance