Question

What is the pressure on the bottom of a garbage can if it holds 70 kg of garbage over an area of 0.5 m^2?

1. 70 Pascals
2. 500 Pascals
3. 35 Pascals
4. 1372 Pascals

Answer 1

You can figure out what the pressure formula is by thinking about it once you understand it.

First, what is pressure? We can agree that if I poke you will a pen or a push you with my hand with the same amount of force, the pressure will be higher with the pin. So the smaller the surface area, the larger the pressure is for the same amount of force. So it makes perfect sense why this formula is true:
\[\LARGE P=\frac{F}{A}\]

Increase the force, the pressure increases. Decrease the area you're pressing, the pressure goes up!

Answer 2

I got 4. is that correct?

Answer 3

That's right.

Answer 4

also is 1 Pa = 1 N/m2 = 0.102 kg/m2