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Lnav1982
Oct21-05, 01:27 AM
I need help please:
A 44.0 kg seal at an amusement park slides from rest down a ramp into the pool below. The top of the ramp is 1.69 m higher than the surface of the water and the ramp is inclined at an angle of 36.3° above the horizontal. If the seal reaches the water with a speed of 4.26 m/s, what is the work done by kinetic friction?

This is what I did:
I drew a free body diagram and Got Efy=N-mgcos(theta)=0 so N=mgcos(theta). For Efx=mgsin(theta)-uKN. Then I plugged N into that problem and solved for uk. So now I am not sure where to go from here. I need kinetic friction which is ukN, but I dont know how to used the other values given to me. Please help me. Thanks

Tide
Oct21-05, 01:58 AM
You might try a different approach. At what speed would the seal hit the water if there were no friction? What can you learn by comparing that with the actual speed?