Physics Question: Boat Deceleration Distance Calculation Help | 30m/s to 0m/s

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To calculate the distance a boat traveling at 30 m/s decelerates to a stop at a rate of 0.6 m/s², the equation v² = v₀² + 2ad is used, where v is the final velocity (0 m/s), v₀ is the initial velocity (30 m/s), a is the acceleration (-0.6 m/s²), and d is the distance. By rearranging the equation and substituting the values, the distance covered before stopping is found to be 750 meters. The confusion arose from not accounting for the negative acceleration properly. Understanding how to isolate variables in equations is crucial for solving such physics problems effectively.
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Sorry to waste your time on wot should be a simple question:

A boat is traveling at 30 metres per second and begins to decelerate at 0.6 metres per second/per second. How much distance would it cover ( in metres) would it cover before it comes to a compete stop?

I have tried solving this with the question v2^2 = v1^2 + 2ad.

v1 = The intial velocity which is 30 metres per second
v2 = The final velocity which I believe is 0 meters per second; a complete stop.
a = The acceleration which is 0.6 metres per second/per second
d = Distance covered

When I try to solve the equation and isolate the variable "d" I get a rediculous answer.

Am I doing something wrong? Is v2 not 0 metres per second? Is this the wrong equation? Do I need to find out other variables such as time to solve this?

All help is appreciated.
 
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lets see here...
V^2=Vo^2+2ad
so
0=900m/s+2(-0.6m/s)(d)
-900/2/(-0.6)=750m=d
750meters :smile:
I hope this helps, I think what you did was not account for the acceleration being negative since you are slowing down..??
 
Thanks mate. Initially I tried it with -0.6 m/s/s but still came out with a nonsense answer. My problem it seems is the mathematics of the problem and being able to isolate "d".

I left school a long time ago and have a vague memory of how to solve basic equations, thankyou for clearing the matter up for me. I will now remember that to swap over something that is being multiplied, you divide the entire left hand side by that value.

Well done.
 
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