- #1
Fusilli_Jerry89
- 159
- 0
a 2.0 kg brick rides on a 20kg sled and is dragged upa22 degree slope by a rope witha tension of 1000 N. Theropeis parallel totheslope. The friction coefficient(both static and kinetic) between the brick and sled is 0.30 and between the sled and the ground is 0.15. Predict each mass's acceleration. I got 0.8 m/s/s for thebrick which I'm sure is right, and for the sled sled I got 40 m/s but the teacher says it is 45 m/s/s.
Teacher's method:
1000-20(9.8)sin22-0.15(22)(9.8)sin22-5.4=20a
a=45.5m/s/s
My method:
1000-81-30-5.4=22a
a=40m/s/s
Teacher's method:
1000-20(9.8)sin22-0.15(22)(9.8)sin22-5.4=20a
a=45.5m/s/s
My method:
1000-81-30-5.4=22a
a=40m/s/s