A completely reversible heat engine operates with a source at 1500 R and a sink at 500 R. If the entropy of the sink increases by 10 Btu/R, how much will the entropy of the source decrease? How much heat, in Btu, is transferred from the source?

Explanation:

Efficiency of reversible engine

= (T₁ - T₂) / T₁ , T₁ and T₂ be temperature of source and sink respectively

= (1500 - 500 )R / 1500R

= 1000 / 1500

= 2 / 3

If Q₁ be heat extracted and Q₂ be heat dumped into sink

efficiency = (Q₁  - Q₂) / Q₁

given Q₂ / T₂ = 10

Q₂ = 10 T₂ = 10 x 500R = 5000BTu

Q₁ - 5000R / Q₁ = 2/3

3Q₁ - 15000R = 2Q₁

Q₁ = 15000BTu

Q₂ = 5000 BTu

Q₁ / T₁ = 15000R/ 1500R

= 10R

Decrease in entropy of source = 10R.

Heat transferred = Q₁ - Q₂

= 15000 - 5000 BTu

= 10000BTu

=

you can cut your hand off if your not

according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it