How to find acceleration without mass?

[trollphysics]

Can someone explain to me how it is done? I know you cancel the m's out in a formula but how?

 

[cepheid]

Welcome to PF.

Your question is too vague for anyone to give a meaningful answer. If there is a specific context in which you need to know how to solve for acceleration, by all means post it.

 

[quietrain]

differientiate velocity with time?

 

[trollphysics]

Welcome to PF.

Your question is too vague for anyone to give a meaningful answer. If there is a specific context in which you need to know how to solve for acceleration, by all means post it.

no i mean like on a slope. My teacher said that you don't need mass if you have M = mu. So on a 45 degree angle ramp. The delta x would be 30m. Then you would need you can cancel out the m's in a equation.

differientiate velocity with time?

no time. Just are given angle, delta x, mu

 

[timthereaper]

I think I understand what the question is. If I understand right, there's a mass on a sloped plane and there's a way to solve for the acceleration of the mass down it in terms of g, mu, and theta.

If you set up a free body diagram of the problem, you'll get the equation ma=mg sin(theta) - mu*N, where N is the normal force. N = mg cos(theta), so when you substitute and cancel the m's everywhere, you get:

a = g sin(theta) - mu*g cos(theta)

I think this is what you mean. In any case, try being more clear in your initial post next time.

 

[Naty1]

You are also implying Einstein's Equivalence Principle...ALL masses accelerate at "g" at the surface of the earth...that is, it happens that gravitational and inertial acceleration are the same...

 

[WitlessWanaBe]

Just a thought, though it may be way off. Related to what Naty said. It sounds to me like the poster might be thinking of formulae for gravitational attraction relative to a specific body of known mass. If so, the process you may be looking for is:

F = (G.m1.m2)/d²
F = ma

So for a given mass:

a = F/m
= ((G.m1.m2)/d²)/m
= Gm/d²

Useful for calculating the orbits of satellites around the Earth or planets around stars etc.