Time to Pass 30m - Joe's Car 4.33s

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Homework Help Overview

The discussion revolves around a problem involving the time it takes for Joe to pass another car on the highway. The scenario describes Joe's initial gain in distance and how this gain increases over time as he accelerates. The subject area includes concepts of motion and acceleration.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants explore the initial conditions of the problem, questioning the application of Newton's laws and the nature of acceleration involved. Some participants identify a pattern in the distance gained over time, while others express confusion about the correctness of the provided answer.

Discussion Status

The discussion is ongoing, with participants sharing different interpretations of the problem and questioning the validity of the given answer. There is an exploration of patterns in the distance gained, but no consensus has been reached regarding the correct solution.

Contextual Notes

Some participants note discrepancies in the expected time to pass based on the distance gained and the acceleration described. There is a suggestion to derive an equation for distance as a function of time, indicating a potential gap in understanding the problem setup.

brendanmeneze
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Joe was driving on the highway a car ahead of him was driving far below the speed limit so he decided to pass. In the first second he gained(gained means to get nearer to something you are chasing) 5m on the car and as he accelerated he gained 1.5 times as much distance in each second as he had the second before. If there was 30 m between joe and the car he was passing then how long did it take him to pass

Correct answer
537/100s


t = 1s
u = s/t=5/1 m/s
a = 1.5 m/s^2



V^2= u^2 +2as

V^2= 5^2+ (2*1.5*2.5)
v = sqrt100=10


v = u + at
10 = 5+ (1.5*t)
10-5=1.5t
t =5/1.5=3.333
t = 3.33+1=4.33 (one second put because of first gained)
 

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brendanmeneze said:
Joe was driving on the highway a car ahead of him was driving far below the speed limit so he decided to pass. In the first second he gained(gained means to get nearer to something you are chasing) 5m on the car and as he accelerated he gained 1.5 times as much distance in each second as he had the second before. If there was 30 m between joe and the car he was passing then how long did it take him to pass

Correct answer
537/100s

Hi brendanmeneze! Welcome to PF! :smile:

I don't think this has anything to do with Newton or with constant acceleration.

In the first second, he gains 5
In the second second, he gains 5*1.5
In the third second, he gains 5*1.5^2
In the fourth second, he gains 5*1.5^3.

Can you see a pattern? :smile:

Anyway, after 4 seconds, he gains 5(1 + 1.5 + 2.25 + 3.375) = over 40 metres.

Have I understood the question right? :confused:
 
Newtons laws motion

you could right there tinytim butt the answers 5.37 s for 30m you got less seconds 4 for more meters 40m unless the answer given 537/100 is wrong. thank you and i believe you are right because laws of motion don't give right answer.
 
brendanmeneze said:
you could right there tinytim butt the answers 5.37 s for 30m you got less seconds 4 for more meters 40m unless the answer given 537/100 is wrong. thank you and i believe you are right because laws of motion don't give right answer.

Yes, I think the answer given is wrong. :frown:

Finish it anyway … can you see the pattern, and get an equation for the distance as a function of time? :smile:
 
thanks tiny-tim for helping me out.
 

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