Suppose you balance a 2-kg ball on the tip of your finger, which has an area of 1 cm2. Show that the pressure on your finger is 20 N/cm2, or is 200 kPa.

Question

anonymous · Answer

I'm assuming this means that your finger is pointed straight up in order to try and balance the ball.

Pressure is simple. It is a force acting over an area. So we can write it as such:$$P = \frac{ F }{ A }$$Now we are given the mass of the ball, so to convert that to a force would be using Newton's 2nd Law:$$F = ma$$

I'll let you go ahead and figure how to combine the two equations to find your pressure. It's pretty straightforward "plug-and-chug" to show what they want you to show.

anonymous · Answer

So would it be 2*9.8/1cm2 =20N/cm2

anonymous · Answer

That's all you need