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Incorrect Pressure

  • Thread starter jefgreen
  • Start date
  • #1
78
0

Homework Statement


A crate, whose bottom surface is 50.4 cm by 28.3 cm, exerts a pressure of 2.50x10^3 Pa on the floor. What is the mass of the crate.


Homework Equations


P=F/A
m=weight/gravity (9.80)


The Attempt at a Solution


2.50x10^3 F
------------=----------------
1 1.4x10^3 cm^2


F=3.5x10^6

m=weight/9.80

m=3.5x10^6
-----------
9.80


Answer: 3.6x10^5 kg

I feel as though I made a mistake somewhere...
 

Answers and Replies

  • #2
rl.bhat
Homework Helper
4,433
7
You have convert the length and the width from cm to meter.
 
  • #3
78
0
so I would multiply 2.50x20^3 by .787 (.283m+.504m)?
 
  • #4
rl.bhat
Homework Helper
4,433
7
so I would multiply 2.50x20^3 by .787 (.283m+.504m)?
What is the formula for area?

.787 (.283m+.504m)
What is this?
 
  • #5
78
0
What is the formula for area?

.787 (.283m+.504m)
What is this?
lxw?
 
  • #6
78
0
A=lxw

So.. (.283m x .504m)= 0.119952. I am not sure about the units, but is this the correct answer?
 
  • #7
78
0
would it be meters squared (m^2)?
 
  • #8
rl.bhat
Homework Helper
4,433
7
A=lxw

So.. (.283m x .504m)= 0.119952. I am not sure about the units, but is this the correct answer?
Now it is correct. Unit of the area is m^2.
Now F = P*A = ........?
 
  • #9
78
0
F=299.88N

so....

m=weight/9.80

therefore m=299.88N/9.80 m/s^2

mass equals.... 30.6kg

Correct?
 
  • #10
rl.bhat
Homework Helper
4,433
7
Correct.
 

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