Q$2)(10$ points$)$ Write the symbol of the closest answer on your answer sheet for the following problems: Hint: use the following values for Air, $C_p=1\mathrm{.}005k\frac{J}{k}g.K,C_V=0\mathrm{.}718k\frac{J}{k}g.K$

An ideal Brayton cycle has a net work output of $150k\frac{J}{k}g$ and a backwork ratio of $0\mathrm{.}4.$ If both the turbine and the compressor had an isentropic efficiency of $85\%,$ the net work output of the cycle would be

$($a$)74k\frac{J}{k}g$

$($b$)95k\frac{J}{k}g$

$($c$)109k\frac{J}{k}g$

$($d$)128k\frac{J}{k}g$

$($e$)177k\frac{J}{k}g$

An Otto cycle has a compression ratio of $8$ and a maximum temperature of $627C.$ At the beginning of the compression stroke, the pressure and temperature of the working fluid are $100$ kPa and $27C.$ Based upon the cold air standard analysis assumptions, how much work is produced per cycle?

a$)43\mathrm{.}7k\frac{J}{k}g$

b$)97\mathrm{.}4k\frac{J}{k}g$

c$)120k\frac{J}{k}g$

d$)85\mathrm{.}6k\frac{J}{k}g$

e$)114\mathrm{.}2k\frac{J}{k}g$

In an ideal Otto cycle, air is compressed from $1\mathrm{.}20k\frac{g}{m^3}$ and $2\mathrm{.}2$ L to $0\mathrm{.}26$ L $,$ and the net work output of the cycle is $440k\frac{J}{k}g.$ The mean effective pressure $($MEP$)$ for this cycle is

$($a$)544$ kPa

$($b$)599$ kPa

$($c$)528$ kPa

$($d$)416$ kPa

$($e$)367$ kPa

Air in an ideal Diesel cycle is compressed from $3$ L to $0\mathrm{.}15$ L $,$ and then it expands d$$ring the constant pressure heat addition process to $0\mathrm{.}30$ L $.$ Under cold air standard conditions, the thermal efficiency of this cycle is

$($a$)35\%$

$($b$)44\%$

$($c$)65\%$

$($d$)70\%$

$($e$)82\%$

Consider an ideal Brayton cycle executed between the pressure limits of $1200$ kPa and $100$ kPa and temperature limits of $20C$ and $1000C$ with argon $(C_p=0\mathrm{.}5203k\frac{J}{k}g*K,C_r=0\mathrm{.}3122k\frac{J}{k}g*K)$ as the working fluid. The net work output of the cycle is

$($a$)68k\frac{J}{k}g$

$($b$)310k\frac{J}{k}g$

$($c$)93k\frac{J}{k}g$

$($d$)186k\frac{J}{k}g$

$($e$)158k\frac{J}{k}g$