so if you push down on a scale and it says 15 pounds does that mean I apply 15 pounds of pressure or is it more complicated than that
In: Physics
If you push down on a scale and it says 15 pounds, this means you are applying 15 pounds of force. However, pressure is different from force. Force is the total push you apply, and it’s measured in pounds (or Newtons in the metric system). Pressure is the force spread over an area, and it’s measured in pounds per square inch (PSI) or similar units.
So, the scale is measuring the force you’re applying, not pressure. To calculate pressure, you would need to know the area over which that 15 pounds of force is being applied.
A scale is a machine designed to measure force. If you use it wrong, it will give you bad results. Most scales work best with a constant force at the center, pushing straight down.
But if you’re using it right? Yeah, not pressure but force – you’re pushing down with the same force as fifteen pounds of stuff.
You apply 15 pounds of force. Weight is the force of gravity pulling on you and can change. You weigh less in the mountains than at sea level. You weigh a lot less in space or on the moon. Not to be confused with mass, which is the amount of stuff that makes up something. That doesn’t change without adding or removing stuff.
Short answer is yes, you are applying 15 pounds of pressure, nothing more complicated than that.
Longer answer: To a physicist, a “pressure” would be a force per area. So you would measure that as pounds per square inch. So your question, to be more precisely phrased, would be:
“ELI5: so if you push down on a scale and it says 15 pounds does that mean I apply 15 pounds of FORCE or is it more complicated than that”
If your physicist was being pedantic, they would also say that “pound” most often refers to a mass, rather than a force, but not always. So they would further re-word your question to be:
“ELI5: so if you push down on a scale and it says 15 pounds does that mean I apply 15 pounds-FORCE of FORCE or is it more complicated than that”
Not pressure, force. Pressure is force divided by area at which this force is applied. If you push with one hand and it says 15 pounds, abd and then you push with the same 15 pounds but with two hands, the pressure will be halved, but force is still the same
Scales are basically a tool to measure force you apply to them. They’re just converting this force to mass, if you use them on earth.
dude it means you applying 15 pounds of pressure but think of it like the scale just tells you how much your pushing down and yeah it’s kinda complicated too
Latest Answers