MTH642 ASSIGNMENT NO 1

         MTH642

ASSIGNMENT NO 1

                                                   Due date: 30 – 11 – 2022

Question no. 1:-

 

A.     What is the difference between gage pressure and absolute pressure?

B.     A vacuum gage connected to a chamber reads 25kPa at a location where the atmospheric pressure is 97 kPa. Determine the absolute pressure in the chamber.

Solutions:-

A.     What is the difference between gage pressure and absolute pressure?

Solution:-

                 The difference b/w the two is that absolute pressure uses absolute zero as its zero point, while gauge pressure uses atmospheric pressure as its zero point. Due to varying atmospheric pressure, gauge pressure measurement is not precise, while absolute pressure is always definite.

B.     A vacuum gage connected to a chamber reads 25kPa at a location where the atmospheric pressure is 97 kPa. Determine the absolute pressure in the chamber.

Solution:-

Given that:-

                 Vacuum pressure = 25kPa

                      Atmospheric pressure = 97kPa

                     Absolute pressure = Vacuum pressure - Atmospheric pressure

                     Absolute pressure = 25 - 97

                    Absolute pressure = -72

Question no. 2:-

Determine the pressure exerted on a diver at 15m below the free surface of the sea. Assume a barometric pressure of 101kPa and a specific gravity of 1.03 for seawater.

Solution:-

             Atmospheric pressure = 101kPa

Distance h from the free surface = 15m

Specific gravity of sea water = 1.03

Distance of sea water p = 1.03 x 1000

                                         = 1030m³/kg

 Pressure exerted on the diver at 15m below the free surface = Pa + pgh

Then,

                pgh = (1030)(9.8)(15)

                        = 151410

So,

Pressure exerted on a diver at 15m below the free surface = 101000 + 151410

                                                                                             = 252410