How much gravity does a human produce?

Question

How much gravity does an average human of say 150 lbs produce?

Also is said gravity still produced on Earth, but not felt because of the gravity of Earth, or does it not get produced at all because of our incorporation into said gravitational force?

Answer 1

The force of gravity between 2 bodies is given by:

F = GMm/r^2

where G = gravitational constant = 6.67E-11 N-m^2/kg^2
M = mass of body 1
m = mass of body 2
r = distance between bodies

Gravity can either be measured as a force, say between two bodies, or as an acceleration.

So, the gravitational acceleration towards any given body is given by:

a = GM/r^2

Let's say a person is the body you want to find the gravitational acceleration for:

M = 150 lbs = about 70 kg
G = 6.67E-11 N-m^2/kg^2
r = whatever:

a = 70*6.67E-11/r^2

a = 4.669E-9/r^2 (m/s^2)

So, depending on how far someone is from a person weighing about 70kg will determine how much gravitational acceleration is pulling on them due to that person.

Example: let's say something is 1 meter away from a 70 kg person, the the gravitational acceleration felt by the object due to that person would be:

a = 4.669E-9 m/s^2

This means that in a gravity free environment (other than the person) that object would be accelerated towards the person at 4.669 m/s every second. Of course, the closer the object gets to the person, the faster it gets pulled in.

Of course, this all assumes the person as a point mass. And as we all know humans have irregular mass distribution and just like any other body in the Universe cannot be properly modeled as a point mass. However, Newton's Law of Gravitation gives a pretty solid approximation to gravitational force/acceleration.

And to answer your other question: Gravity is produced by everything that hass mass. Because the earth is so large and creates so much gravity (about 9.81 m/s^2 of gravitational acceleration on average at the surface) The gravity created by humans, animals, plants, and anything else pales in comparison and is therefore not discernable from Earth's gravity.

Answer 2

Every object has gravity so to speak, a better way to put would be that every object has a force interaction will all other objects regardless of distance. Using the equation F=(G*m*M)/d^2 where G is the gravitional constant (6.6726E-11 m3 kg-1 s-2), m is the mass of one object, M is the mass of the other and d is the distance between the objects.

So say I weigh 68.03 kg (about 150 lbs) and so do you and we are currently 1,609,344 m (1000 miles) apart then the Force between us would be 9.33E-13, which is pretty freaking small, but we still do exhibit a force between each other, its just so happens the earth which is a heck of alot more massive dominates this force between us.

So every object exhibits a force and every object regardless of mass, size, or location, I could be 1000 light years away and yet I would still have a force on you, no where in the universe can you escape gravity, there might be places were all the gravitional forces cancel each other out, but the absence of gravity is impossible.

Answer 3

NONE