Net force given 40 degree angle, coef. of kinetic friction=.3, and mass=80kg

1. Oct 16, 2007

pebbles

1. The problem statement, all variables and given/known data

angle is in relation to horizontal

2. Relevant equations
f net=m*a

3. The attempt at a solution

yikes! i don't know!

i appreciate ANY help!

2. Oct 16, 2007

Staff: Mentor

Please write one's work and show an attempted solution. Is the angle above or below the horizontal - it makes a difference.

Please refer to - http://hyperphysics.phy-astr.gsu.edu/hbase/N2st.html#c2 - for some ideas.

A mass m has weight W = mg, and that weight (which is normal to the horizontal) will have a friction force f = $\mu$mg, where $\mu$ = coefficient of friction.

Now the external (applied) force at a angle can be resolved into horizontal and vertical forces.

When the horizontal applied force exceeds friction, the net force (Fnet causes the mass m to accelerate a.