Did I do this question correctly?

[izelkay]

Homework Statement

http://cyclotron.tamu.edu/dhy/sample_exam1_phys218.pdf

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?

 

[TSny]

Looks good!

 

[izelkay]

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?

 

[TSny]

That sounds good, too. Or, you could use work and energy concepts if you're familiar with them.

 

[izelkay]

Awesome; thanks. We haven't gotten to the work and energy stuff yet.

 

[TSny]

OK. Good work!