Force to Pascals: Solving Homework Statement

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To calculate pressure in pascals, the formula used is force divided by area. The weight of 145 lbs converts to 65.8 kg, but the contact area must be in square meters, not cubic centimeters, as the latter measures volume. The correct conversion of area is essential for accurate calculations. The initial attempt yielded an incorrect pressure of 21.9 pascals, while the book states the correct answer is 21.5 x 10^3 pascals. Focus on using the correct units for area to achieve the right result.
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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
 
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Whalstib said:

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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