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Force to Pascals

  • Thread starter Whalstib
  • Start date
  • #1
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0

Homework Statement





In my chemistry class we have been given a formula:

force/area = Newton/m^2 = kg/ms^2 = pascal

Often I find a problem given the following info and answer:

what is the pressure exerted by someone weighing 145lbs with contact area of 300 cubic cm?

Now the formula dealing with Kg (145lbs = 65.8 kg) also has time involved with it.

How do apply this eqn. to obtain an answer in pascals?

Homework Equations



I can only apply force/area

The Attempt at a Solution



I'm making mistakes as I go...I'll get back with a closer one quickly!

Book says:
21.5 x 10^3 pa
 

Answers and Replies

  • #2
berkeman
Mentor
57,470
7,489

Homework Statement





In my chemistry class we have been given a formula:

force/area = Newton/m^2 = kg/ms^2 = pascal

Often I find a problem given the following info and answer:

what is the pressure exerted by someone weighing 145lbs with contact area of 300 cubic cm?

Now the formula dealing with Kg (145lbs = 65.8 kg) also has time involved with it.

How do apply this eqn. to obtain an answer in pascals?

Homework Equations



I can only apply force/area

The Attempt at a Solution



65.8/.300 = 21.9 pascals WRONG!

Book says:
21.5 x 10^3 pa
The contact area cannot be in units of cubic cm. That is a measure of volume.

Don't worry about the time units in the force equation, just stick with forces and areas to calculate pressure. Be careful with your units, and you should get the right answer.
 

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