DE for modelling motion of a box

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acrusera
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So if you were to slide a box-like object down a straight ramp with a single gradient (its literally just an incline no curve). And you attempt to model it accurately would this be correct?
Given the DE
ma=mg-kv
where a=dv/dt, mg=force of gravity, kv= force of friction

Anyway my main question, is k the coefficient of kinetic friction? Does k=μ?
 
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What is µ according to you? Coefficient of static friction? then no ,k≠ µ
 
acrusera said:
So if you were to slide a box-like object down a straight ramp with a single gradient (its literally just an incline no curve). And you attempt to model it accurately would this be correct?
Given the DE
ma=mg-kv
where a=dv/dt, mg=force of gravity, kv= force of friction

Anyway my main question, is k the coefficient of kinetic friction? Does k=μ?

I think you've got your equations mixed up.

##ma = mg - kv##

Is for a body falling under gravity with air resistance proportional to its velocity.
 
PeroK said:
Is for a body falling under gravity with air resistance proportional to its velocity.
k=##6 \pi \eta r## ??
then what about the ramp?
 
The "coefficient of friction", [itex]\mu[/itex] is the number that multiplies the normal force on an object to give the friction force. An object of mass m, has weight mg. On a ramp making angle [itex]\theta[/itex] with the horizontal, we can divide the weight into components parallel to and normal to the ramp. The component normal to the ramp is [itex]mg cos(\theta)[/itex].