Calculate Force in Newtons From 95 lb Weight Falling 1m

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Discussion Overview

The discussion revolves around calculating the force in Newtons from a weight given in pounds, specifically for a person weighing 95 pounds falling 1 meter. Participants explore the conversion between units of force and mass, as well as the application of gravitational acceleration in the calculation.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions how to convert pounds to mass and whether to use gravitational acceleration in the calculation.
  • Some participants assert that pounds are units of force and suggest converting them to Newtons before applying gravitational acceleration.
  • Another participant mentions the existence of 'slugs' as a unit of mass in the US and provides a conversion factor from pounds to kilograms.
  • There is a request for a detailed calculation to illustrate the process of determining the force upon impact after falling 1 meter.
  • One participant expresses confusion about the distinction between pound force and pound mass, indicating a need for clarification on unit conversions.

Areas of Agreement / Disagreement

There is no consensus on the correct approach to convert pounds to Newtons or how to apply the gravitational constant in the calculation. Multiple competing views on unit conversions and the definitions of weight and mass are present.

Contextual Notes

Participants express uncertainty regarding the appropriate conversions and calculations, highlighting the potential confusion between different units of measurement and their applications in physics.

Oh the irony
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Alright, well.
How do I get mass out of pounds?
I need to figure out what the force is in Newtons on someone when they fall 1 meter.

The person weighs 95 pounds.

Do I need to convert it to kilograms then divide that by the gravitational constant of 9.81 m/s?

or can I just do 95/9.81?


1/1 = 1m/s^2

0 ~ 1 / 1s = 1m/s^2

9.7 x 1 = 9.7

F = 9.7


First I did speed, which was 1/1 (1 meter for 1 second) = 1m/s^2

Then I did acceleration, and then M x A = 9.7

Is it correct?



NOTE: This is not homework.
 
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Pounds are units of force, like Newtons, so you'd convert them to Newtons first, then divide by the 9.81 [m/s^2]. Converting pounds to kilograms would be as meaningless as converting Newtons to kilograms.

The unit of mass in the US is called 'slugs'. I've never seen them used before personally. But you could convert slugs to kilograms.
 
Pythagorean said:
Pounds are units of force, like Newtons, so you'd convert them to Newtons first, then divide by the 9.81 [m/s^2]. Converting pounds to kilograms would be as meaningless as converting Newtons to kilograms.

The unit of mass in the US is called 'slugs'. I've never seen them used before personally. But you could convert slugs to kilograms.


How do I convert them to Newtons? I did

95/ 9.81 = 9.7

so isn't the force 9.7 Newtons? or how do i get Newtons?
 
Oh the irony said:
How do I convert them to Newtons? I did

95/ 9.81 = 9.7

so isn't the force 9.7 Newtons? or how do i get Newtons?

The equation is:

F = ma
(force) = (mass)*(acceleration)

some examples of this in both systems:

Newtons = (grams) * (meters/second^2)

or:

pounds = (slugs)*(miles/hour^2)

In this case, the acceleration a is g, so a = g.

So F = mg, therefore, the force is your value before dividing by g. So, as I said, convert the force from pounds to Newtons, then divide by gravity.

You can easily do this conversion by typing "x pounds in Newtons" into google
 
lol I'm not really understanding, its only possible for me to learn if someone does the whole calculation and I can actually see it.


Can you do it for me?

The object is falling for 1 second and went 1 meter in that 1 second.

I want to know the force that it hits the ground.

can you show all the math please?
 
The normal unit of mass in english units is a slug, but it's common to specify "pound mass" as opposed to "pound force". The weight of a person is commonly expressed in pounds (force) or in kilograms (mass), without causing confusion. To answer your question:

1 pound_mass = 0.45359237 kilograms
 

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