Acceleration given velocity and distance

AI Thread Summary
The discussion revolves around calculating the average acceleration of a driver during a collision after a car traveling at 90 km/h strikes a tree. The calculated acceleration is -363.37 m/s², which converts to approximately -37.08 g's when divided by 9.81. Participants confirm that negative acceleration is valid in this context, as it indicates deceleration. There is a debate about whether the negative value is acceptable and if there are any rules regarding negative g's. Ultimately, the consensus is that the calculations are correct, and negative g's can accurately represent the situation.
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Homework Statement


A car traveling at 90 km/h strikes a tree. The front end of the car compresses and the driver comes to rest after traveling 0.86 m. What was the average acceleration in g's of the driver during the collision?

Homework Equations


The Attempt at a Solution


The acceleration in m/s/s is -363.37 but I tried dividing by 9.8 and I got -37.05 g's but evidently that's wrong. I'm not sure what I'm missing here, I converted the km/h into m/s/s then got the correct acceleration then devided by 9.81. Is there a rule that I didn't use? Is there a limit on negative gs?
 
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You are right, the acceleration is -363.37 m/s/s.

I'm not a hundred percent sure, but I think -37.08 g's is actually correct. Because if one g is worth 9.8 m/s/s, and you had positive 37.08 of them, your acceleration would be in the positive direction. But it's not... so I see no problem with having a negative number there.

Is there another reason you think -37 g's is wrong?
 
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