A 3 kg block is being pulled by a string at a constant speed on a surface with a coefficient of kinetic friction of 0.3. If the string is at an angle of 30 degrees with the horizontal, what is the magnitude of the force necessary to pull the block?
friction force=.3*(3g-Fsin30)
pulling force=friction=Fcos30
.9g-.3Fsin30=Fcos30
.9g=F(.3sin30+cos30)
solve for F