Solve this---Question (i): Question Stem: A gas trapped in a frictionless piston cylinder device is subjected to the following energy interaction for 30 seconds. The electric resistance draws 0.1 Amp from a 100-V source, the paddle wheel work of 30 J, and 1 kJ of heat is transferred into the gas from the candle. The volume of the gas increases by 6L during the process. If the inside pressure is 100 kPa and piston is weightless, Solve for the net transfer of energy into the system ΔEsys. [5 marks]

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We have a gas trapped in a piston-cylinder device with multiple energy interactions. The electric resistance draws 0.1 amperes from a 100-volt source for 30 seconds. A paddle wheel does 30 joules of work on the gas. Heat of 1 kilojoule is transferred from a candle into the gas. During this process, the gas volume increases by 6 liters against a constant pressure of 100 kilopascals. We need to find the net energy transfer into the system. Let's calculate the electrical work input. The electric resistance draws 0.1 amperes from a 100-volt source. The power is voltage times current, which equals 100 volts times 0.1 amperes, giving us 10 watts. Since this operates for 30 seconds, the total electrical work is 10 watts times 30 seconds, which equals 300 joules. This work is done on the system, so it's positive energy input. Now let's calculate the boundary work done by the gas. The gas volume increases by 6 liters, which equals 0.006 cubic meters, against a constant pressure of 100 kilopascals or 100,000 pascals. The boundary work is pressure times volume change, which equals 100,000 pascals times 0.006 cubic meters, giving us 600 joules. Since this work is done by the system on the surroundings, it represents energy leaving the system, so it's negative. Now let's apply the energy balance equation. The net energy transfer into the system equals energy inputs minus energy outputs. We have three energy inputs: electrical work of 300 joules, paddle wheel work of 30 joules, and heat transfer of 1000 joules. We have one energy output: boundary work of 600 joules. Therefore, the net energy transfer is 300 plus 30 plus 1000 minus 600, which equals 730 joules. This is our final answer. We have a gas trapped in a piston-cylinder device with multiple energy interactions. An electric resistance draws 0.1 amperes from a 100-volt source for 30 seconds. A paddle wheel does 30 joules of work on the gas. Heat of 1 kilojoule is transferred from a candle to the gas. The gas expands by 6 liters against a constant pressure of 100 kilopascals. We need to find the net energy transfer into the system. First, let's calculate the electrical work. The electrical work is given by voltage times current times time. With 100 volts, 0.1 amperes, and 30 seconds, we get 100 times 0.1 times 30, which equals 10 watts times 30 seconds, giving us 300 joules of electrical work input to the system. Next, we calculate the boundary work done by the gas during expansion. The boundary work equals pressure times volume change. With a pressure of 100 kilopascals, which is 100,000 pascals, and a volume increase of 6 liters, which is 0.006 cubic meters, we get 100,000 times 0.006 equals 600 joules. This is work done by the gas on the surroundings, so it's an energy output from the system. Now we apply the first law of thermodynamics. The change in system energy equals energy inputs minus energy outputs. Our energy inputs are: heat from the candle at 1000 joules, electrical work at 300 joules, and paddle wheel work at 30 joules, giving total work input of 330 joules. The energy output is boundary work of 600 joules. Therefore, the net energy transfer is 1000 plus 330 minus 600, which equals 1330 minus 600, giving us 730 joules. In summary, we solved this energy transfer problem by identifying all energy interactions with the gas system. The electrical work contributed 300 joules, the paddle wheel work added 30 joules, and heat transfer from the candle provided 1000 joules, giving us a total energy input of 1330 joules. The gas did 600 joules of boundary work on the surroundings. Therefore, the net energy transfer into the system is 1330 minus 600, which equals 730 joules. This represents the increase in internal energy of the gas.