"In many harbors, old automobile tires are hung along the sides of wooden docks to cushion them from the impact of docking boats. the tires deform in accordance with Hooke's law. as a boat is brought to a stop by gently colliding with the tires, the rate of deceleration of the boat is:"
The answer is "increases until the boat stops"
because
"The force changes with the displacement of the tires. The greater the displacement, the greater the force, the greater the magnitude of acceleration as per the formula F=-kdx=ma"
**My issue is this. The boat would stop after some deformation/displacement of the tires and the tires would push the boat back. That is, after that maximum deformation/displacement is reached the tire would start regaining its original shape and dx would be decreasing. Therefore, you would have decreasing deceleration.
So, wouldn't the better answer be "increases and then decreases before the boat stops"?
Maybe it is thinking too deeply but in physics I feel like we always speak of net displacement. The boat hasn't finished moving when the tires are experiencing maximum deformation/displacement just as a ball, thrown in the air, hasn't finished moving once it has reached its maximum height.
In terms of physics in general and the mcat, what do you think? Am I thinking too deeply here?
Thanks in advance.
The answer is "increases until the boat stops"
because
"The force changes with the displacement of the tires. The greater the displacement, the greater the force, the greater the magnitude of acceleration as per the formula F=-kdx=ma"
**My issue is this. The boat would stop after some deformation/displacement of the tires and the tires would push the boat back. That is, after that maximum deformation/displacement is reached the tire would start regaining its original shape and dx would be decreasing. Therefore, you would have decreasing deceleration.
So, wouldn't the better answer be "increases and then decreases before the boat stops"?
Maybe it is thinking too deeply but in physics I feel like we always speak of net displacement. The boat hasn't finished moving when the tires are experiencing maximum deformation/displacement just as a ball, thrown in the air, hasn't finished moving once it has reached its maximum height.
In terms of physics in general and the mcat, what do you think? Am I thinking too deeply here?
Thanks in advance.
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