Answer :
D) 151.95 kJ. The work done by air which enters into an evacuated vessel from the atmosphere when the valve is opened.
Given:
- Atmospheric pressure [tex](P_{atm})[/tex] = 1.013 bar
- Volume of air entering [tex](V_{air})[/tex] = 1.5 m³
The work done by the air is given by the formula:
W = P * V
Where:
- P is the atmospheric pressure
- V is the volume of the air entering the vessel
First, convert the atmospheric pressure to Pascals (SI unit):
1 bar = 10⁵ Pascals
So, 1.013 bar = 1.013 × 10⁵ Pascals
Now, substitute the values into the work formula:
W = 1.013 × 10⁵ Pa × 1.5 m³
W = 151950 Joules
Convert Joules to kilojoules (kJ):
151950 Joules = 151.95 kJ
Since the work is done by the air on the surroundings, it is typically considered positive. Therefore, the correct answer is: (d) 151.95 kJ
Corrected complete question
What is the work done by air which enters into an evacuated vessel from atmosphere when the valve is opened ? The atmospheric pressure is 1.013 bar and 1.5m³ of air at atmospheric condition enters into the vessel.
(a) 100.2 kJ
(b) 120.5 kJ
(c) 140.65 kJ
(d) 151.95 kJ