Automobile Hydrostatic Pressure

[SAT2400]

Homework Statement

1) A typical automobile tire has a gauge pressure of around 30 Ib/in^2. How much is that in pascals? If a car weighs 8897N(=2000lb), how much area(SI units) on each tire is in contact with the road?

2) A swimming pool 5m wide by 10m long is filled to a depth of 3m. What's the total force exerted on the bottom due to the water?

3) GIven that most people cannot suck water up a straw any higher than about 1.1m, what's the lowest gauge pressure they can creat in the lungs?

Homework Equations

F=PA
F=P(4A)

PA=F

P= p(h2O)gh

The Attempt at a Solution

1) 2.1 x 10^5 Pa and .011m^2 are answers..I didn't get these answers though..
2) 1.5 x10^6 n is the answer
3) -1.1 x10^4 Pa is the answer..

Please help me to get these answers by giving me steps and equations.
Thank you!

 

[rl.bhat]

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