Question 4 continued
(d) A cylinder, closed at one end is sealed by a movable piston, as
shown in figure 3. Initially, the cylinder contains 0.25 litres of air
at absolute pressure 100 kPa, and at the ambient temperature
of the surroundings, 300K.
F
Figure 3: Piston and Cylinder (Axial Section)
A force, F, is applied which moves the piston until the volume
trapped is 0.01 litres. Calculate the temperature and pressure
of the air at the end of the process, and the work done on the
gas if;
(i) The process takes place very slowly, with no insulation be-
between the air in the cylinder and the surroundings.
(4 Marks)
(ii) The process takes place very quickly, with perfect insula-
tion between the air in the cylinder and the surroundings
(5 Marks)
You may assume that;
$R = 287 \frac{J}{kgK}$
$C_v = 718 \frac{J}{kgK}$
$C_p = 1005 \frac{J}{kgK}$
$\gamma = 1.4$
(Total 25 Marks)