 #1
Physicsit
Ok I have been workoing on this problem for at least a couple of hours with no luck
A 1.0kg block is released from rest at the top of a curved frictionless track as shown in the figure below. (a) What are the speeds of the block at points A and B? (b) If the block goes on a level surface at point C with a coefficient of kinetic friction of 0.50, how far from point C will the block come to rest?
Attached is a graphical representation
Here is what I did so far
KE =1/2mv^2
M= 1.0 kg
V= ?
Wsubg= mgh
For point A
Final Kinetic energy = KEInitial  W subg
W sub g = mgh 1.0 X 9.8 X 2.0
Kfinal = 20
201/2(1.0)v^2
40= v^2
v= 6.3 m/s that is v of point a
for point b
Initial kenetic = 20
Final Kinetic energy = KEInitial  W subg
W sub g = mgh 1.0 X 9.8 X 6.0
final kentic = 6020=40
40=1/2(1.0)v^2
80=v^2
v 8.9 m/s for point b
I then calculated the maximum static firction
using the coefficient of kinetic friction of 0.50
mg X coefficient friction
1.0X9.8X.50=4.9N
that is the maximum force that can be exerted wihtout the objectmoving
but I do not know how to claculate how far from point C will the block come to rest
I do not know if I did the first three parts correct either
I have been at this for a while now over 2 hours
I desperatley need help any advice would be much appreciated
A 1.0kg block is released from rest at the top of a curved frictionless track as shown in the figure below. (a) What are the speeds of the block at points A and B? (b) If the block goes on a level surface at point C with a coefficient of kinetic friction of 0.50, how far from point C will the block come to rest?
Attached is a graphical representation
Here is what I did so far
KE =1/2mv^2
M= 1.0 kg
V= ?
Wsubg= mgh
For point A
Final Kinetic energy = KEInitial  W subg
W sub g = mgh 1.0 X 9.8 X 2.0
Kfinal = 20
201/2(1.0)v^2
40= v^2
v= 6.3 m/s that is v of point a
for point b
Initial kenetic = 20
Final Kinetic energy = KEInitial  W subg
W sub g = mgh 1.0 X 9.8 X 6.0
final kentic = 6020=40
40=1/2(1.0)v^2
80=v^2
v 8.9 m/s for point b
I then calculated the maximum static firction
using the coefficient of kinetic friction of 0.50
mg X coefficient friction
1.0X9.8X.50=4.9N
that is the maximum force that can be exerted wihtout the objectmoving
but I do not know how to claculate how far from point C will the block come to rest
I do not know if I did the first three parts correct either
I have been at this for a while now over 2 hours
I desperatley need help any advice would be much appreciated
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