But Pressure is Funner

zcabral

Homework Statement

An automobile tire is inflated with air originally at 10.0°C and normal atmospheric pressure. During the process, the air is compressed to 26.0% of its original volume and the temperature is increased to 32.0°C.
(a) What is the tire pressure?

p1V1/t1=p2v2/t2

The Attempt at a Solution

i know this is simple but I am just not getting the right answer I keep using p1V1/t1=p2v2/t2 but wrong answers come out. i used 1 atm for normal atmospheric pressure

Homework Helper
Remember that T must be in Kelvin since you are dividing by it.

zcabral
yes it is in kelvin...i got 419903.5 is that right?

Homework Helper
Temperature hasn't changed much in absolute terms
volume has gone down by a factor of 4 - so we want a pressure of around 4 atm.

V1 = 1
V2 = 0.26
P1 = 1atm
T1 = 283K
P2 = ?
T2 = 305K

1/283 = 0.26 P /305
So P = (305 /283) / 0.26 = 4.1 atm or around 420KPa

ps. That's an impressive number of significant figures given the data!

zcabral
it asks for it in pa that's y