Question

The gauge pressure for the air in a balloon equals 1.01 x 10^5 Pa. If atmospheric pressure is equal to 1.01 x 10^5 Pa, what is the absolute pressure of the air inside the balloon?
a.

0 Pa

b.

5.05 x 10^4 Pa


c.

1.01 x 10^5 Pa

d.

2.02 x 10^5 Pa

Answer 1

Answer:

D.        2.02 x $10^{5}$ Pa

Explanation:

The gauge pressure is the pressure measured relative to the atmospheric pressure.

Absolute pressure (or total pressure), is the sum of the gauge pressure and the atmospheric pressure. i.e

$P_{ABS}$ = $P_{G}$ + $P_{ATM}$

Where;

$P_{ABS}$ = absolute pressure

$P_{G}$ = gauge pressure = 1.01 x $10^{5}$Pa  (from the question)

$P_{ATM}$ =  atmospheric pressure = 1.01 x $10^{5}$Pa

Substitute these values into the equation above;

$P_{ABS}$ = $P_{G}$ + $P_{ATM}$

$P_{ABS}$ = 1.01 x $10^{5}$ + 1.01 x $10^{5}$

$P_{ABS}$ = 2.02 x $10^{5}$ Pa

Therefore, the absolute pressure of the air inside the balloon is 2.02 x $10^{5}$ Pa

Answer 2

Absolute Pressure = Atmospheric Pressure + Gage Pressure

Absolute Pressure = 1.01 x 10^5 Pa + 1.01 x 10^5 Pa = D. 2.02 x 10^5 Pa