Please help me. I have no idea how you even start this

A 30 kg block slides down a 20° ramp with an acceleration of 1.2 m/s2. What is the coefficient of kinetic friction between the block and the ramp?

Question

Please help me. I have no idea how you even start this

A 30 kg block slides down a 20° ramp with an acceleration of 1.2 m/s2. What is the coefficient of kinetic friction between the block and the ramp?

dancing_stars23 · Answer

@NoelGreco @Zeronknight @zepp

kainashi · Answer

m = 30 kg
(theta) = 20
a = 1.2 m/s^2

I believe the equation you should start with is 

$$F _{T}=ma$$

with 
$$F_t=F _{gravity}+N _{normal force}+F _{down incline}+F _{kinetic friction}=0$$

zepp · Answer

The first thing would be representing the question in a drawing, so you may better understand what you're trying to find.

dancing_stars23 · Answer

i am still confused

johnweldon1993 · Answer

|dw:1456285363141:dw|

Draw the free body diagram of the box with all the forces acting on it

|dw:1456285477349:dw|

The find the resulting force components and add them all remembering

$$\large \Sigma F_x = ma_x$$
$$\large \Sigma F_y = ma_y$$

Eventually you will solve for the friction force knowing $\large f_k = \mu _kN$ you are solving for $\large \mu _k$