hmm let's see: i did (1/2(0.0385)(5.5)^2 - 0.0385(9.81)(1) ) all over -3.15 (because h =1 and the distance is 1/sin18.5. So my answer is -0.65 ?? is that right?
i got PEg (gravitational) - w (since the direction of friction force is against the displacement) = kef . And then i have w= fd; so f= (kf-peg) over -d. so that's equal to (1/2mv(final) ^2 - mgh) all over -d. Now I am stuck ?
A 38.5g block is sliding at 5.0m/s on the upper surface which is frictionless and 1.00m above the lower frictionless surface. The block slides down a ramp that is at an angle of 18.5 degrees. What must the friction force on the ramp be in order for the block to have a velocity of 5.5m/s at the...