3. A newly built engine operates between the
room temperature (21 oC) and the melting point of
silver (961 oC) and claims to have an actual
efficiency of 75.0 %.
a) How much mechanical energy per cycle does
the engine deliver if it absorbs 3.50 x 106 J of heat
everycycle (from the hot bath) assuming this claim
is true?
b) How much thermal energy does the engine
reject per cycle to the colder reservoir at 21o C
if the claim is true?
c) What is the maximum thermal efficiency of
an ideal Carnot cycle operating between the same
two reservoirs? Do you think that the engine's
claim is justified based on this? Explain.
d) What is the change in entropy of the universe that actual engine produces per cycle (assuming that
the claim of 72% efficiency is true)? Do you think
that the engine's claim is justified based on this?
Explain
3. A newly built engine operates between the room temperature (21 oC) and the melting point...
A Carnot engine is operated between two heat reservoirs at temperatures of 520 K and 300 K. a) If the engine receives 6.45 kJ of heat energy from the reservoir at 520 K in each cycle, how many joules per cycle does it reject to the reservoir at 300 K? b) How much mechanical work is performed by the engine during each cycle? c) What is the thermal efficiency of the engine?
A Carnot engine is operated between two heat reservoirs at T1= 435 K and T2= 308 K. (a) If the engine receives 5113 J of heat from the reservoir at T1 in each cycle, how many joules per cycle does it deliver to the reservoir at T2? (b) How much mechanical work is performed by the engine during each cycle? (c) What is the thermal efficiency of the engine?
A heat engine operates in a Carnot cycle between 86.0°C and 345°C. It absorbs 20,000 J of energy per cycle from the hot reservoir. The duration of each cycle is 5.00 s. (a) What is the mechanical power output of this engine? (b) How much energy does it expel in each cycle by heat?