Posted by Kristy on .
I'm so confused on how to find mu. A 68 kg box slides down a 27 degree ramp with an acceleration of 3.10 m/s squared. The acceleration due to gravity is 9.81 m/s squared. It wants me to find mu between the box and the ramp but I don't even know where to start. Can you please walk me through it?

Physics 
Taylor,
I'm assuming by mu you mean the coefficient of friction, u(subk)
to find it just sum your forces in the x and y directions and solve for u(subk)
use the formula
sum of the forces = mass x acceleration