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Did I do this question correctly?

  • Thread starter izelkay
  • Start date
  • #1
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Homework Statement


http://cyclotron.tamu.edu/dhy/sample_exam1_phys218.pdf [Broken]

For Number 2 Part a


Homework Equations


v0 = 1.7 m/s
F = ma
v = 0m/s
v² = v0² + 2aΔx


The Attempt at a Solution


Spent like 30 minutes trying to use a constant acceleration kinematics equation, but nothing seemed to work without knowing either the time or the acceleration.
Then I remembered that F = ma, and the problem gave me the force (9.8*10^4N) and the mass (3.6*10^7kg). So I solved for a, and got -0.00272 m/s².

I plugged this acceleration into v² = v0² + 2aΔx and solved for Δx, and I got 530.82 meters. Is this correct? If not, can anyone help me understand what I did wrong?
 
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Answers and Replies

  • #2
TSny
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Looks good!
 
  • #3
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For C of that question, would I use the final velocity I obtained from part b as the new initial velocity, and 0 as the final velocity, solve for acceleration using v² = v0² + 2aΔx (Δx being 1.5m), and multiply that acceleration by the mass of the tanker?
 
  • #4
TSny
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That sounds good, too. Or, you could use work and energy concepts if you're familiar with them.
 
  • #5
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Awesome; thanks. We haven't gotten to the work and energy stuff yet.
 
  • #6
TSny
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OK. Good work!
 

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