need some help with conversion !!

This is mostly a math problem.
But I'm lost.

A car travels for 2 hrs with an average velocity of 50 mph. The radius of the cars wheels are 28 cm. How many times did the front wheels have to turn to cover such distance? Round up to a whole number;ignore sig figs; Find circumference of the wheels using C=2*r*n (n=3.141563)
I got C= 175.93 cm
but don't know what to do now,
ANy help would appreciated.

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Re: need some help with conversion !!

[quote="riverrat"]This is mostly a math problem.
But I'm lost.

A car travels for 2 hrs with an average velocity of 50 mph. The radius of the cars wheels are 28 cm. How many times did the front wheels have to turn to cover such distance? Round up to a whole number;ignore sig figs; Find circumference of the wheels using C=2¶r (¶=3.141563)
I got C= 175.93 cm
but don't know what to do now,
ANy help would appreciated.[/quote]
Now all you need to do is convert the distance covered (100 miles) into metres.
Then divide that number by 1.7593 (note the change of decimal place because 100cm = 1m), and you'll have the number of turns of the wheel.

I don't know what the conversion for miles into metres is - you should have learned it in class, if not then I'm sure it's googleisable.

btw, are you from america? I've never met anybody from the UK call maths 'math'.

Thanks and I am from america, I did'nt know that people in the UK say "maths" we say math!

Thanks alot!! )

Its definitly "math" here. My calculus TA (from many years ago) from India use to say "[b]maths[/b]" and "I'm too hungover, hand in your [b]homeworks[/b] and go enjoy the day"

1 mile = 1609.344 meters (approx. 1.61 km)

I think we say math[b]s[/b] because it's mathematic[b]s[/b] rather than mathematic

But there is probably some other reason, deep seated in latin or greek or something...

Appearently Bill Gates says the correct useage is "math". "maths" recieves a red squiggly line under it in microsoft word, as does "metres". Maybe he should call it "American" instead of "English". But then again, no one here knows what a metre is and most are clueless beyond alegbra. We tried to adopt the SI units, that is until serious problems arose when construction workers and contractors said 1 meter/metre = 1 yard (3 feet). I could only imagine the pandemonium when a 200 metre bridge came up 17 meters short of the other side.

[quote="scarf"]Appearently Bill Gates says the correct useage is "math". "maths" recieves a red squiggly line under it in microsoft word, as does "metres". Maybe he should call it "American" instead of "English". But then again, no one here knows what a metre is and most are clueless beyond alegbra. We tried to adopt the SI units, that is until serious problems arose when construction workers and contractors said 1 meter/metre = 1 yard (3 feet). I could only imagine the pandemonium when a 200 metre bridge came up 17 meters short of the other side.[/quote]
If you look at the language selection (assuming the American version of Word has a choice of languages), you can select British English or US English.
Obviously, we use British English over here (far superior...) which erases those red squiglies.

As for metres into yards, I always say it's about 1:1. But I can get away with it because I never need to be accurate (indeed, I never use yards for anything other than when giving approximite distances from the Car park in which I work to the ticket office. The older generation in this country still tend to use yards).

Further to this (paraysing) amusement, despite having grown up learning exclusively metric (which is sooooo much easier for maths/science), I still use miles/gallon for fuel consumption, quote miles for distances by road (kilometers when I'm hiking, because it's compatable with OS maps), speeds in miles/hour, I weigh myself in stones (no, not pounds; I [b]never[/b] use pounds, but I [i]sometimes[/i] use kilos], and measure my height in feet & inches. I also order pints of milk (and cider if I'm in a drinking mood), not litres. I suppose its from before I went to school, what I originally grew up with.

Funnily enough, (again!) am I correct in saying that an american gallon is different to a UK gallon?

my calculator says (1 UKgal = 1.2.... gal). Strange, I never knew. Temperature wise, i think it makes more sense to use Farenheit, as the scale gives you a more accurate idea of the weather. However, really cold temperatures I use K, and really hot (above 40 C) i use C. Thats out of habit of programing furnace controllers from 300 C to 1600 C for the last 4 years when I cook samples. I prefer miles, because thats what all the street signs are in (even though speedometers in cars usually have kmph usually smaller on the inner part of the scale). Anything smaller than an inch, I only think in metric. 1/16th of an inch, what a joke. Friggin learn metric I tell them, and give it to me in mm. I'd like people to measure height in centimeters, as the plain meter scale is too large. I'd much rather be 190.5 centimeters than 1.9 meters. I guess it all boils down to what you're familiar with, and what you have a feel for.

Regaurdless, when I talk to friends or family, its plain old pounds / feet / gallons / farenheit. Any other unit is like ebonics spoken to the queen.

At least we all agree upon arabic numerals/seconds/Roman calender

[quote="scarf"]my calculator says (1 UKgal = 1.2.... gal). Strange, I never knew. Temperature wise, i think it makes more sense to use Farenheit, as the scale gives you a more accurate idea of the weather. However, really cold temperatures I use K, and really hot (above 40 C) i use C. Thats out of habit of programing furnace controllers from 300 C to 1600 C for the last 4 years when I cook samples. I prefer miles, because thats what all the street signs are in (even though speedometers in cars usually have kmph usually smaller on the inner part of the scale). Anything smaller than an inch, I only think in metric. 1/16th of an inch, what a joke. Friggin learn metric I tell them, and give it to me in mm. I'd like people to measure height in centimeters, as the plain meter scale is too large. I'd much rather be 190.5 centimeters than 1.9 meters. I guess it all boils down to what you're familiar with, and what you have a feel for.

Regaurdless, when I talk to friends or family, its plain old pounds / feet / gallons / farenheit. Any other unit is like ebonics spoken to the queen.

At least we all agree upon arabic numerals/seconds/Roman calender[/quote]
Oh yea, I forgot about temperature.
I exclusively use celcius (not centigrade...) because that makes most sense. Close to zero, it's cold. Close to 30, a boiling hot summers' day (:lol:), although in chemistry I'll use Kelvin if I'm going to be using equations (so for practically everything except melting point data)

As for everything else, well... metric time would be [i]easier[/i], eg for working out ms[sup]-1[/sup] from mh[sup]-1[/sup], and various other things. Same with years.
I propose 100 centons in a centit, 100 centits in a decer and 20 decers a day (not that metric, but 100 major units per day? no chance)
then 10 months, like we used to have before juleus and augustus, and perhaps we'll [i]have[/i] to pass on having a metric number of days, else our seasons would all mess up...

Or perhaps not :lol:

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