The maximum thermal efficiency of any power cycle operating between hot and cold reservoirs at 10008C and 5008C, respectively, is .

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )

Acircular ring of charge with radius b has total charge q uniformly distributed around it. what is the magnitude of the electric field at the center of the ring? 0 keq/b2 keq2/b2 keq2/b none of these answers

On his honeymoon, james joule attempted to explore the relationships between various forms of energy by measuring the rise of temperature of water which had fallen down a waterfall on mount blanc. what maximum temperature rise would one expect for a waterfall with a vertical drop of 20 m? the specific heat of water is 4186 j/kg ∙ k. a)0.064 c° b)0.053 c° c)0.071 c° d)0.047 c°