Mass removed from pistons Perfectly insulated negligible between the piston and
ID: 546638 • Letter: M
Question
Mass removed from pistons Perfectly insulated negligible between the piston and the cyinder wals. The block is removed from each piston, the piston moves upward dand tne added or feieosed Idcal gas A is isothermally cxpanded. ideal gas B is adiabatically expandod s bins surroundings? Explain your recsoning in a few sentences. Draw an arraw on each figure indicating the drection c d heat involved in this process affect the intemal energy of the 7. In the figure above, two cylinders are filled with the same ideal gas. A piston is fit so that no gas escapes; friction is a. In each case, does the gas do work or is work done on the gos? Expiain your reasoning. b. is there a larger transfer of thermal energy as heat between Gas A and the surroundings or between Gas COC For the expansion of Gas B, how do the work and heat involved in this process affect the internal energy of the gas? Exploin your reasoning c. For the expansion of Gas A, how do the work an gas? Explain your reasoning. le absorbs guatiorn 5.2, w d. Thus, we can calculate the quant heat together with its measured TABLE 5.2 lists the of liquid water is higt water affects F sistant toExplanation / Answer
a.) In each case expansion takes place i.e piston moves upward which has been possible because of the work done by the gas to rise the piston
b) In case A , expansion is happening isothermally this means no change in internal energy. Using first law of thermodynamics q = U + w , since chnage in internal; energy is 0 => q= w . since work is done by gas therefore heat is provided to the system.
In case B, adiabatic expansion takes place that means no exchange of heat is occuring => q = 0
c) In case A isothermal expansion is happening, therefore change in internal energy is 0 so whatever heat is provided will be used for work done by gas. Hence there will be no effect of heat and work involved on internal energy
d) In case B adiabatic expansion takes place ,no heat is provided to the system therefore work done by the gas will be at the expense of decrease in internal energy of the system.