IA#2 Review – Kinematics on Inclined Planes & Static Friction February 6, 2013
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Oral Drill
A man applies a 35 N force to push a 5 kg suitcase up a 30° ramp into the baggage check-in area at the airport. If k = 0.10, what is the acceleration of the suitcase up the ramp? (sin30 = 0.5, cos30 = 0.866). FAFA m θ kk a = ?
+y +x FANG SAT Fg Fgx Fgy FNFN FAFA FfFf
Setup M (do not fully solve in class but you will solve for HW) Y-direction Fnet = ma F N - F gy = ma SOLVE X- direction Fnet = ma -F A + F gx +F f = ma SOLVE
Independent Practice
STATIC FRICTION
Expectations for Paired Reading Take turns reading each paragraph Annotate (including summarizing) each paragraph
Reading Debrief What is static friction? What is the difference between static friction and kinetic friction? What equation would I use to solve for static friction?
Reading Debrief Remember back to our mu-shoe lab. We had to apply a force to a shoe on different surfaces. The force we applied was the highest amount of force we could apply before the shoe just started to move. In this case, what formula would we use to determine the static friction force? (Hint – at this point, the applied force is opposing the maximum static friction force.)