I think this is another momentum question

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The discussion revolves around calculating the average force exerted by a car to stop a hailstone that created a dent. Key parameters include the hailstone's mass of 0.012 kg, its velocity of 20 m/s, and the dent's depth of 0.20 cm. Participants suggest using the work-energy theorem as a more straightforward approach than momentum or kinematics. They discuss deriving acceleration and force using the formula v^2 = -2*a*s, but emphasize that energy methods simplify the calculation. The conversation highlights the importance of understanding the impact duration and the correct application of physics principles in solving the problem.
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i really have no clue what to do in this problem since there's a measurement for the dent...what formula am i supposed to use for this?4. During an autumn storm, a 0.012kg hail stone traveling at 20.0m/s made a 0.20 cm deep dent in the hood of Darnell’s new car. What average force did the car exert to stop the damaging hail stone?
so far i understand:
mass= .012kg
velocity= 20 m/s
and then there's the .20 cm deep dent but i dun knoe what's that need for?
 
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You could probably use momentum or kinematics, but the work-energy theorem is a better place to start
 
Can you describe, in detail, the trajectory that the hailstone has travelled, and everything that's happened to it?
 
Would it be right to use v^2=-2*a*s to find the acceleration and then force

If you do not know v^2=u^2+2as try to derive it using:

v=u+at

s=ut+at^2/2
 
ponjavic said:
Would it be right to use v^2=-2*a*s to find the acceleration and then force

If you do not know v^2=u^2+2as try to derive it using:

v=u+at

s=ut+at^2/2

But its a lot easier with energy. W=-KE0
Fd=KEo
F=KEo/d=mv^2/2d
Everything you need to plug in is given, using acceleration is reproving the work energy theorem with kinematics.
 
We had a similar problem in our physics class, but my physics teacher says the solution is incorrect.
1) How long was the impact, if it traveled .2 cm at 20 m/s? (This is the part that is incorrect.)
2) Ft=m(v_2-v_1)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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