UPS delivery man is loading his truck by shoving the parcels up a ramp. The ramp is inclined at an angle of 30 degrees above the horizontal. He sends a parcel of mass 15 kg, up this ramp. the coefficient of sliding friction is .10 and gravitational force is class standard (10).(adsbygoogle = window.adsbygoogle || []).push({});

AThe magnitude of the kinetic friction acting on the parcel is?

BHe sends parcel up ramp with initial Kinetic Energy, E, so that by the time, the parcels up the ramp, it has 0 KE. Ramp is length 1.0m.

CTo give this parcel this initial KE, he most do WORK on the parcel. Assuming he pushed it a short distance of .75m what is the average force he needs to apply. Ignore friction for this part.

The work I have done is:

A

Y Components: N-MG Cos 30 --> N=150 Cos 30 --> N=129.9

Friction = [tex]\mu[/tex]k * N --> .10 * 129.9 ---> Magnitude =12.99

B

1/2 M V_{o}^{2}+ [STRIKE]MGH[/STRIKE]= [STRIKE]1/2 M V_{f}^{2}[/STRIKE] + MGH

1/2 M V_{o}^{2}= MGH

H= Sin30 -->.5

1/2 (15) (V)^{2}= 75

V=3.16

So initial KE = 75 ?????

C

Is related to B so if that's wrong this is wrong.

Work = Force * Displacement

Work = KE

KE: 75 / Disp: .75 = Force: 100N

Thanks for your help.

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# Homework Help: Kinetic Energy, Work Done, and Inclines

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