Luigi Fortunati

2023-02-18 08:37:48 UTC

What is the difference between the force accelerating the mass (F=ma)

and the force deforming the mass (Hooke)?

Can a force accelerate mass without deforming it?

[[Mod. note --

1. Deformation can be quasi-static or dynamic, whereas acceleration

is necessarily dynamic.

2. That depends on the force and the body-being-accelerated. If the

force is somehow applied equally to each part of the body (e.g.,

a uniform gravitational field in the Newtonian perspective), then

the body can be accelerated without any deformation. Or, if the

body is either very small or very stiff, and/or the acceleration

is very small, then the deformation may be negligibly small.

An important limiting case of this is the acceleration of a point

mass, which we define as a mass with no internal structure; a point

mass doesn't deform under acceleration. Electrons are a well-known

example. But if a force is applied to a macroscopic body, and is

*not* applied equally to each part of the body, then yes, the body

will deform.

-- jt]]

and the force deforming the mass (Hooke)?

Can a force accelerate mass without deforming it?

[[Mod. note --

1. Deformation can be quasi-static or dynamic, whereas acceleration

is necessarily dynamic.

2. That depends on the force and the body-being-accelerated. If the

force is somehow applied equally to each part of the body (e.g.,

a uniform gravitational field in the Newtonian perspective), then

the body can be accelerated without any deformation. Or, if the

body is either very small or very stiff, and/or the acceleration

is very small, then the deformation may be negligibly small.

An important limiting case of this is the acceleration of a point

mass, which we define as a mass with no internal structure; a point

mass doesn't deform under acceleration. Electrons are a well-known

example. But if a force is applied to a macroscopic body, and is

*not* applied equally to each part of the body, then yes, the body

will deform.

-- jt]]