1. The problem statement, all variables and given/known data The 40 kg crate shown in the Figure below rests on a horizontal plane for which the coefficient of kinetic friction is mk = 0.3. If the crate is subjected to a 350 N towing force as shown, determine the speed of the crate 3 seconds after starting from rest. + given angle of 30 degrees http://i.share.pho.to/49e78c92_o.png 2. Relevant equations F=ma where F is force (N) m is mass (kg) a is acceleration (m/s^2) v=a/t v is the final velocity a is the (average) acceleration t is the time the body accelerates (sec) combing them gives: v(final) = Ft/m 3. The attempt at a solution v(final) = 350N(3sec)/(40kg) = 26.25m/s? but it is wrong, the answer is v = 17.8m/s Notes: 1. I don't know how they got an answer of 17.8m/s...I didn't use the kinetic friction value (0.3) and angle given (30 degrees)... 2. Also when questions say 'speed', do they mean that you should find 'velocity'? In this case are they similar? Even though velocity is just speed with a direction? 3. What goes through your mind before solving these types of problems? Are there steps? I.e. step 1. identify what is given , step 2. identify what is missing I'm not really strong with the area of physics, especially statics and dynamics, so a simple explanation with all the steps would be great Thank you in advance for your help!