How do you convert m/s^2 to km/h?

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Discussion Overview

The discussion revolves around the conversion of acceleration from meters per second squared (m/s²) to kilometers per hour (km/h), and the related calculations for determining final velocity in a specific problem involving a bus's acceleration. The scope includes conceptual understanding, mathematical reasoning, and practical application in a homework context.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants note that m/s² is a unit for acceleration, while km/h is a unit for speed, indicating a fundamental difference that complicates direct conversion.
  • One participant suggests that conversion is possible if the time interval is known, implying a relationship between acceleration and speed over time.
  • Another participant provides a method for converting speed from m/s to km/h, detailing a specific calculation that they find reliable.
  • A participant presents a problem involving a bus's initial speed and acceleration, sharing their calculations for final velocity but expressing confusion over the correctness of their answer.
  • Several participants discuss the necessity of converting units to SI units (m/s) before performing calculations, emphasizing the importance of unit consistency.
  • One participant shares their conversion of 29 km/h to m/s and subsequent calculations, but expresses uncertainty about the accuracy of their final result.
  • Another participant reflects on the practical experience of acceleration duration, suggesting that real-world context can influence understanding of the problem.

Areas of Agreement / Disagreement

Participants generally agree on the need to convert units for consistency in calculations, but there is disagreement regarding the specific calculations and results, with some participants expressing confusion and others providing differing interpretations of the problem.

Contextual Notes

There are unresolved issues regarding the accuracy of calculations and the interpretation of time intervals in relation to acceleration. Some participants express uncertainty about their results, indicating potential errors in unit conversion or arithmetic.

Kdawg
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How do you convert m/s^2 to km/h?
 
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At least in the form you asked the question, you can't. m/s2 is a unit for acceleration while km/h is a unit for speed.
 
well you can if you have the delat t of a
 
But if you are trying to convert ms^-1 than its rather easy, there's a couple ways of doing it.
I do it like such
((36km/60)/60)*1000
which is equal to 10ms^-1

there's some really easy way to do it, but this one never fails and it doesn't take that much longer so i just use this one.
 
Oh, that would make sense wouldn't it, lol. I am trying to figure out this problem.
A bus traveling at +29 km/h accelerates at a constant +3.7 m/s2 for 6.3 s. What is its final velocity in km/h?
This is my work so far, what am I doing wrong.
Vi = 29Km/h
a = 3.7m/s^2
t = 6.3s
Vf = ?

Vf = Vi + at
Vf = 29 + 3.7 * 6.3
Vf = 52 - With right sig figs
 
Looks good to me.
 
Thats what I thought but the damn webassign keeps marking it wrong.
 
I can see why from here,
Vf = Vi +at
SI UNITS!
Velocity SI unit is ms^-1
Therefore 29kmh^-1
Needs to be converted to ms^-1
 
What is its final velocity in km/h?
And then convert it back
 
  • #10
You have to remember to convert stuff, i will never forget, i lost 15 marks out of 50 on my last exam from not converting to the SI units
 
  • #11
I converted 29km/h to 8.0556m/s the multiplied 8.0556 + 3.7 * 6.3 = 30.6256
then converted that to 110. That obviously isn't right, what am I doing wrong.
 
  • #12
Bleah. Of course. I wasn't looking at the units.
 
  • #13
Seems right to me... Remember, think of how long 6.3 seconds is when your accelerating in a car. Like when you go onto a freeway, you would really only accelerate for about 3 seconds to get to 100km, from about 50..., so 6 seconds is actually a long time to accelerate for
 
  • #14
Kdawg said:
I converted 29km/h to 8.0556m/s the multiplied 8.0556 + 3.7 * 6.3 = 30.6256
then converted that to 110. That obviously isn't right, what am I doing wrong.


Try evaluating this again I don't seem to get the same answer for 8.05556+(3.7*6.3) as you do.

(and hence the converted figure is different as well)
 
  • #15
KaneOris said:
Seems right to me... Remember, think of how long 6.3 seconds is when your accelerating in a car. Like when you go onto a freeway, you would really only accelerate for about 3 seconds to get to 100km, from about 50..., so 6 seconds is actually a long time to accelerate for

This really depends on how hard you put your foot on the accelerator (or how good your car is!)
 
  • #16
Yes, but you know what i mean, 6.3 seconds is a long time to accelerate, although the sound of it isn't very much, its a pain in the A$$ if you look at your watch and wait for 6 or 7 seconds to pass...
 

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