If the force required to remove the lid is 480 N and the atmospheric pressure is 1.0 × 10^5 Pa?
what is the internal air pressure?
attempt: I used the formula p=F/A and got 6.23 Pa. is this correct?
Update:A partially evacuated airtight container has a tight-fitting lid of surface area 77m^2 and negligible mass. If the force required to remove the lid is 480N and the atmospheric pressure is 1.0 x 10^5Pa, what is the internal air pressure?
Answers & Comments
Verified answer
So how big is the lid?
Yikes! 77 m² Are you sure about that? I was expecting a can of beans, not a container with a lid with diameter more than 16 feet across!
{ Force outside on lid due to atmospheric pressure = 1.0 x 10^5 * 77 = 7,700,000 N }
Pressure = force / area
Pressure difference between inside and outside of container = (force needed to remove lid) / area
= 480 N / 77 m² = 6.234 Pa
Pressure difference between inside and outside of container = outside pressure - inside pressure
6.234 Pa = 1.0 x 10^5 Pa - inside pressure
inside pressure = 100000 Pa - 6.234 Pa = 99993 Pa = 9.9993 x 10^4 Pa