Prove that for an isolated system, there is no change in internal energy.

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An automobile having a mass of 1100 kg initially moves along a level highway at 110 km/h relative to the highway. It then climbs a hill whose crest is 40 m above the level highway and parks at a rest area located there. Use a reference with kinetic and potential energy each equal to zero for the stationary highway before the hill.Let g = 9.81 m/s2. For the automobile, determine its change in kinetic energy and its change in potential energy, both in kJ.

A system which has neither mass-5 nor energy transfer across the * boundary is called a Closed System Isolated System Open System None System O

3. The movement of a piston in a cylinder is restrained by a spring with a spring constant K=250lbf/in. At a position of x=0 the force exerted by the spring on the piston is 0lbf. How much work is done (in Btu) on the spring by the piston when the piston has moved 2in (compressed the spring 2in)? a.Sketch the problem. b.Draw lines identifying the control volume, or control mass. c.Identify the states with numbers, letters, or descriptions such as “in” and “out”. d.Write down the knowns and unknowns. e.Identify what is being asked for f.State all assumptions.

3.  In the rotational frame, work done between two instances of rotational states is nothing but the difference in rotational kinetic energy between those states        True        False

A gas is contained in a vertical piston-cylinder assembly by a piston with a face area of 50 in² and weight of 100 lbf. The atmosphere exerts a pressure of 14.7 lb/in² on top of the piston. A paddle wheel transfers 3 Btu of energy to the gas during a process in which the elevation of the piston increases slowly by 2 ft. The piston and cylinder are poor thermal conductors, and friction between the piston and cylinder can be neglected. Determine the work done by the gas on the piston, in Btu, and the change in internal energy of the gas, in Btu. * Your answer is incorrect. Determine the expansion work done by the gas on the piston, in Btu. Wexp = i 0.854 Btu

A gas in a piston-cylinder assembly undergoes a process during which its volume reduces from 2 m to 1 m°. During this process, the system specific volume does not change O increases twice O reduces twice

A closed system loses energy by heat transfer at the rate of 10KJ/s. If the system operates at steady state, calculate power in this process.

A gas is contained in a vertical piston-cylinder assembly by a piston with a face area of 60 in2 and weight of 100 lbf. The atmosphere exerts a pressure of 14.7 lbf/in² on top of the piston. A paddle wheel transfers 3 Btu of energy to the gas during a process in which the elevation of the piston increases slowly by 2 ft. The piston and cylinder are poor thermal conductors, and friction between the piston and cylinder can be neglected. Determine the work done by the gas on the piston, in Btu, and the change in internal energy of the gas, in Btu. Step 1 Determine the expansion work done by the gas on the piston, in Btu. Wexp = i Btu