Voorletters en Van Initials and Surname Studente nommer Student number Datum / Date MTX221 2011 KLASTOETS 3E / CLASSTES 3E 25 min. (14 punte/marks) *Sal herwerk tot 10 punte vir klaslys doeleindes * Will be worked back to 10 marks for class list purposes n Suier/silinder bevat 1.1 kg H 2 O teen 80ºC en 10% kwaliteit (toestand 1). Aanvanklik rus die suier of die stopvlak (sien figuur). Hitte word toegevoeg tot die suier die onderste stopvlak net-net verlaat. By hierdie oomblik is die druk 500 kpa (toestand 2). Verdere hitte word toegevoeg tydens n politropiese proses (n = -0.8) tot die druk 600 kpa is (toestand 3). Tydens hierdie proses neem die H 2O volume toe selfs al vermeerder die massa op die suier. Bepaal die volgende: a) Die aanvanklike volume en druk b) Die temperatuur van toestand 2 c) Die finale temperatuur (toestand 3) d) Die totale arbeid verrig e) Stip die prossesse op n P-v diagram. Dui T, P en v waardes aan vir slegs toestand 3. A piston/cylinder contains 1.1 kg H 2 O at 80ºC and 10% quality (state 1). Initially the piston rests on the stop (see figure). Heat is added until the piston just leaves the bottom stops. At this moment the pressure is 500 kpa (state 2). Additional heat is added during a polytropic process (n = -0.8) until the pressure is 600 kpa (state 3). During this process the H 2O volume increases even though the mass on the piston is increased. Determine the following: a) The initial volume and pressure b) The temperature of state 2 c) The final temperature (state 3) d) Total work done e) Plot the processes on a P-v diagram. Indicate T, P and v values for state 3 only. Figuur / Figure Uitreksel uit Formule Blad / Extract from Formulae Sheet: HANDIG DIE VRAESTEL OOK IN ASB PLEASE HAND THE QUESTION PAPER IN AS WELL
Voorletters en Van Initials and Surname Studente nommer Student number Datum / Date MTX221 2011 KLASTOETS 3F / CLASSTES 3F 25 min. (14 punte/marks) *Sal herwerk tot 10 punte vir klaslys doeleindes * Will be worked back to 10 marks for class list purposes n Suier/silinder bevat 1.2 kg oorverhitte H 2 O teen 250ºC en 500 kpa (toestand 1). n Afwaartse krag word op die suier toegapas deur n lineêre veer (sien figuur). Hitte word verwyder en die H 2 O trek in tot die suier die stopvlak net-net raak (die druk neem met 10% af) (toestand 2). Verdere hitte word verwyder tot die druk 200 kpa is (toestand 3). Die maksimum ingeslote volume is 0.2 m 3 wanneer die suier die stop-vlakke raak. Bepaal die volgende: a) Die aanvanklike volume b) Die druk en temperatuur van toestand 2 c) Die finale temperatuur (toestand 3) d) Spesifieke arbeid verrig tussen toestande 2 en 3. e) Stip die prossesse op n P-v diagram. Dui T, P en v waardes aan vir elke toestand. A piston/cylinder contains 1.2 kg superheated H 2 O at 250 C and 500 kpa (state 1). A downward force is exerted on the piston by a linear spring (see figure). Heat is removed and the H 2 O contracts until the piston just touches the stops (the pressure value decreases by 10%) (state 2). Additional heat is removed until the pressure is 200 kpa (state 3). The maximum enclosed volume is 0.2 m 3 when the piston touches the stops. Determine the following: a) The initial volume b) The pressure and temperature of state 2 c) The final temperature (state 3) d) Specific work done between states 2 and 3. e) Plot the processes on a P-v diagram. Indicate T, P and v values for each state. Figuur / Figure Uitreksel uit Formule Blad / Extract from Formulae Sheet: HANDIG DIE VRAESTEL OOK IN ASB PLEASE HAND THE QUESTION PAPER IN AS WELL
Voorletters en Van Initials and Surname Studente nommer Student number Datum / Date MTX221 2011 KLASTOETS 3G / CLASSTES 3G 25 min. (14 punte/marks) *Sal herwerk tot 10 punte vir klaslys doeleindes * Will be worked back to 10 marks for class list purposes n Suier/silinder bevat 1.3 kg H 2 O teen 90ºC en 10% kwaliteit (toestand 1). Aanvanklik rus die suier of die stopvlak (sien figuur). Hitte word toegevoeg tot die suier die onderste stopvlak net-net verlaat. By hierdie oomblik is die druk 500 kpa (toestand 2). Verdere hitte word toegevoeg tydens n politropiese proses (n = -0.4) tot die druk 600 kpa is (toestand 3). Tydens hierdie proses neem die H 2O volume toe selfs al vermeerder die massa op die suier. Bepaal die volgende: a) Die aanvanklike volume en druk b) Die temperatuur van toestand 2 c) Die finale temperatuur (toestand 3) d) Die totale arbeid verrig e) Stip die prossesse op n P-v diagram. Dui T, P en v waardes aan vir slegs toestand 3. A piston/cylinder contains 1.3 kg H 2 O at 90ºC and 10% quality (state 1). Initially the piston rests on the stop (see figure). Heat is added until the piston just leaves the bottom stops. At this moment the pressure is 500 kpa (state 2). Additional heat is added during a polytropic process (n = -0.4) until the pressure is 600 kpa (state 3). During this process the H 2O volume increases even though the mass on the piston is increased. Determine the following: a) The initial volume and pressure b) The temperature of state 2 c) The final temperature (state 3) d) Total work done e) Plot the processes on a P-v diagram. Indicate T, P and v values for state 3 only. Figuur / Figure Uitreksel uit Formule Blad / Extract from Formulae Sheet: HANDIG DIE VRAESTEL OOK IN ASB PLEASE HAND THE QUESTION PAPER IN AS WELL
Voorletters en Van Initials and Surname Studente nommer Student number Datum / Date MTX221 2011 KLASTOETS 3H / CLASSTES 3H 25 min. (14 punte/marks) *Sal herwerk tot 10 punte vir klaslys doeleindes * Will be worked back to 10 marks for class list purposes n Suier/silinder bevat 0.9 kg oorverhitte H 2 O teen 300ºC en 600 kpa (toestand 1). n Afwaartse krag word op die suier toegapas deur n lineêre veer (sien figuur). Hitte word verwyder en die H 2 O trek in tot die suier die stopvlak net-net raak (die druk neem met 25% af) (toestand 2). Verdere hitte word verwyder tot die druk 225 kpa is (toestand 3). Die maksimum ingeslote volume is 0.25 m 3 wanneer die suier die stop-vlakke raak. Bepaal die volgende: a) Die aanvanklike volume b) Die druk en temperatuur van toestand 2 c) Die finale temperatuur (toestand 3) d) Die totale arbeid verrig e) Stip die prossesse op n P-v diagram. Dui T, P en v waardes aan vir elke toestand. A piston/cylinder contains 0.9 kg superheated H 2 O at 300 C and 600 kpa (state 1). A downward force is exerted on the piston by a linear spring (see figure). Heat is removed and the H 2 O contracts until the piston just touches the stops (the pressure value decreases by 25%) (state 2). Additional heat is removed until the pressure is 225kPa (state 3). The maximum enclosed volume is 0.25 m 3 when the piston touches the stops. Determine the following: a) The initial volume b) The pressure and temperature of state 2 c) The final temperature (state 3) d) Total work done e) Plot the processes on a P-v diagram. Indicate T, P and v values for each state. Figuur / Figure Uitreksel uit Formule Blad / Extract from Formulae Sheet: HANDIG DIE VRAESTEL OOK IN ASB PLEASE HAND THE QUESTION PAPER IN AS WELL
XXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX REMOVED DUE TO PRINTING ERROR ON TEST 3F 2W3 = 0 J (HALF MARK) XXXXXXX XXXXXXXXX XXXXXXXX XXXXXX XXXXXX DUE TO PRINTING ERROR IN Q d. THIS TEST TOTAL IS REDUCED TO 12 MARKS, BUT WILL STILL BE REWORKED TO 10.
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