Energy (J) 4 3 2 +. +. -1 -2 K, + U, +Wt= K, + U, + AE %3D ext

A 75 W light bulb is used for 12 hours a day. The electricity for this bulb comes from a natural gas fired power plant that operates with 49% efficiency. How much CO₂ is emitted per day to power this light bulb? Make a simple estimate of the CO2 emissions from the power plant, ignoring transmission losses. 0.0024 kg CO2/day Xx 0.0024 We mentioned earlier in the course that energy technologies in developing countries often have much lower efficacies than those in developed countries. Let's look at one example, lighting via kerosene lamps, which are common in developing countries but about 150x less effective than incandescent lightbulbs at turning energy into useful light. If a family wanted just one tenth of the light provided by the 75 W lightbulb, they'd need to consume 15x as much power, or 1125 W. If a family ran 1125 W worth of kerosene lamps for just 2 hours each day, how much CO2 would this emit? You may assume that kerosene produces the same emissions as gasoline. 3.00 kg…

3. The specific Helmholtz Free energy f is related to the specific internal energy u as: f(T, a) = u - Ts where the "natural variables" of fare temperature and specific volume. a. Expand the differential off in terms of partial derivatives with respect to the natural variables of f b. Using the result from a. and applying the 1st Law of Thermodynamics, what are af af Tand да ila? ap c. From the equality of mixed partial derivatives, show that ƏT = Əs θα |T

5. For a system, the thermodynamic as)vn energy U is defined as a function of S, V, and n which is U(S,V,n) = kn3V 3e3nR %3D where S is the entropy, V is the volume, n is the number of moles, K is the constant, and R is the gas constant. Determine a. Based on the theory in Thermodynamics, (), T = Determine, b. Based on the theory in Thermodynamics, Pressure P = . S,n 5/8 Determine c. Determine ne d. Determine dU in dS, dV and dn