- #1
Naeem
- 194
- 0
A block of mass m = 4.5 kg rests on a frictionless floor. It is attached to a spring with a relaxed length L = 3 m. The spring has spring constant k = 16 N/m and is relaxed when hanging in the vertical position. The block is pulled d = 3 m to one side. In this problem, the block is always constrained to move on the floor (i.e. it never leaves the floor).
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a) By what amount is the spring extended?
DL = m *
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b) What is the potential energy stored in the spring?
Uspring = J *
12.3 OK
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c) The block is released but is constrained to move horizontally on the frictionless floor. What is the maximum speed it attains?
|v|max= m/s *
2.34 OK
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Let's change the problem a bit. When the spring is vertical (hence, unstretched), the block is given an initial speed equal to 1.8 times the speed found in part (c).
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d) How far from the initial point does the block go along the floor before stopping?
Dmax = m *
4.287 OK
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e) What is the magnitude of the acceleration of the block at this point (when the spring is stretched farthest)?
|a| = m/s2
0.638 NO
HELP: What is the force exerted by the spring on the block when the spring is fully stretched?
I am not able to figure out part e. I'm stuck
here is what I did F = ma = k * delta L
Plugged in m , k and delta L
found a to be 8.25 m/s2, which is wrong, anybody tell me what is wrong?
--------------------------------------------------------------------------------
a) By what amount is the spring extended?
DL = m *
--------------------------------------------------------------------------------
b) What is the potential energy stored in the spring?
Uspring = J *
12.3 OK
--------------------------------------------------------------------------------
c) The block is released but is constrained to move horizontally on the frictionless floor. What is the maximum speed it attains?
|v|max= m/s *
2.34 OK
--------------------------------------------------------------------------------
Let's change the problem a bit. When the spring is vertical (hence, unstretched), the block is given an initial speed equal to 1.8 times the speed found in part (c).
--------------------------------------------------------------------------------
d) How far from the initial point does the block go along the floor before stopping?
Dmax = m *
4.287 OK
--------------------------------------------------------------------------------
e) What is the magnitude of the acceleration of the block at this point (when the spring is stretched farthest)?
|a| = m/s2
0.638 NO
HELP: What is the force exerted by the spring on the block when the spring is fully stretched?
I am not able to figure out part e. I'm stuck
here is what I did F = ma = k * delta L
Plugged in m , k and delta L
found a to be 8.25 m/s2, which is wrong, anybody tell me what is wrong?