How far has it traveled in this time?

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The discussion revolves around solving a physics homework problem involving a 747 jetliner that is slowing down on a runway. The key points include the need to apply Newton's Second Law of Motion to determine acceleration, which is not zero, and is calculated to be 1.22 m/s². For part (a), the formula v = u + at is suggested to find the speed after 7.5 seconds, while for part (b), the formula s = ut + 0.5at² is recommended to calculate the distance traveled in that time. The conversation emphasizes the importance of correctly identifying the acceleration and applying the appropriate equations. Understanding these concepts is crucial for solving the problem effectively.
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I need help on this one homework problem.

A 747 jetliner lands and begins to slow to a stop as it moves along the runway. If its mass is 3.50 x 10^5 kg, its speed is 27.0 m/s, and the net breaking force is 4.30 x 10^5 N,

a) what is it speed 7.50s later
b) How far has it traveled in this time?

I don't know what equation or formula to use. I also don't know how to relate the force into the problem. The only thing that I know is the accerleration is zero because the jet is breaking.

Can someone please help me on what equation I should use to slove for the answer,
 
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And the "only thing you know" is very wrong.

The acceleration is not zero. If acceleration were zero, then the jet would maintain a constant velocity.

Do you have the mass of the jet? Do you have the "net force" on the jet? (Yes you do). Does "Newton's Second Law of Motion" ring a bell?
 
ok so
the accerleration= 1.22 m/s square

can I use
(x=finial y postion) = (Xo=initial y postion) + (Vox= initial velocity of X component)(t=time) + 1/2(a=accerleration)(t=time)square

X = Xo + Voxt + 1/2 a t^2Can I use this to find where the jet is at 7.5 second later?
 
Newton's Second Law is F=ma, hence a=m/F, giving a value of 0.81m/s squared in this case.
Now you can use v=u+at for part a) where u=27m/s, a=0.81 and t=7.5.
For part b) you could use the formula s=ut+0.5a(t^2). Hope that helps.
 
Oops sorry your acceleration value is correct, my mistake. Everything else should be ok, sorry.
 
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