How would you calculate this?

platinum87 said:
54mph is better than m/s because m/s requires too many decimal places.

That question should be changed to kph instead of mph

If i can say 1 mile = 1.6, than i can also just assume pi = 3.0, mavity can just be 9 meters per second per second...

And we can all just commit suicide after all of that.
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No because SI units help you in physics.

Conversions become easy, scientific equations start working without the need to convert again and they are understood across the world.
 
muon said:
No because SI units help you in physics.

Conversions become easy, scientific equations start working without the need to convert again and they are understood across the world.
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Paradoxically, SI units are not so good for day to day life.

The unit sizes are all wrong.

"Imperial" (Or Avoirdupois) is much better for many day to day purposes because the unit size is nearer to what people actually use. This is because it is a system of weights and measures that evolved over time to meet peoples real day to day needs in life and trade.

Even in Engineering, Av has many advantages over SI

(Consider, which is an easier specification to work with. 3" +/- 1 thou Or 75mm +/_ 0.05mm, 25PSI or 0.1723 MPa, 25FtLbs or 34Nm, and so on. )

And indeed, AV units are still in common engineering and industrial usage.

(So an Engineering student does need to be familiar with both)
 
A UK engineering student doesn't need to be familiar with non SI units (generally).

Also tell the Americans that SI is the only units to use! :o
 
Orionaut said:
Even in Engineering, Av has many advantages over SI

(Consider, which is an easier specification to work with. 3" +/- 1 thou Or 75mm +/_ 0.05mm, 25PSI or 0.1723 MPa, 25FtLbs or 34Nm, and so on. )

And indeed, AV units are still in common engineering and industrial usage.

(So an Engineering student does need to be familiar with both)
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You've just picked round imperial units.

Also why us 25ftlb easier than 34Nm?

Metres and its 10^x equivalents are much easier in my opinion.
 
First leg: 3 * 50 = 150 miles travelled
Second leg: 2 * 60 = 120 miles travelled

Total miles travelled: 150 + 120 = 270 miles

Average speed: 270 miles / 5 hours = 54mph

Miles per hour to kilometres per hour: 54mph * 1.6 = 86.4 kph

Kilometres per hour to metres per hour: 86.4kph * 1000 = 86,400 metres per hour

Metres per hour to metres per minute: 86,400 / 60 = 1,440 metres per minute

Metres per minute to metres per second: 1,4400 / 60 = 24 metres per second (m/s)
 
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Thanks again for the help all, I got 29/36 for the question and a 71% for the test in general, I lost a ton of points because I read a question wrong. If I'd have read it right it would've been 91%.

It's not as good as I would've wanted but that's what you get for leaving things to the last minute and having to rush through it all I guess.
 
muon said:
You've just picked round imperial units.

Also why us 25ftlb easier than 34Nm?

Metres and its 10^x equivalents are much easier in my opinion.
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Someone mentioned previously on here about imperial and that its better for working with when you dont have the modern luxury of a calculator, as its all fractions.

In this modern age of easy calculator access decimalising things makes sense as long decimals arent a problem to work with any more.

As units of measurement go theres nothing more than tradition between them, mph kph and m/s are all equally valid measurements of speed but because we're raised on mph our comparisons of what the distance really means or what the speed really means are solely based on experience with any given unit.

Si units make sense as others have said when it comes to standardisation and linking things together in a way that requires least conversion. The one i find hilarious though is people confusing pressure when the car sticker reads in kpa and the airgun in bar.
 
Orionaut said:
Paradoxically, SI units are not so good for day to day life.

The unit sizes are all wrong.

"Imperial" (Or Avoirdupois) is much better for many day to day purposes because the unit size is nearer to what people actually use. This is because it is a system of weights and measures that evolved over time to meet peoples real day to day needs in life and trade.

Even in Engineering, Av has many advantages over SI

(Consider, which is an easier specification to work with. 3" +/- 1 thou Or 75mm +/_ 0.05mm, 25PSI or 0.1723 MPa, 25FtLbs or 34Nm, and so on. )

And indeed, AV units are still in common engineering and industrial usage.

(So an Engineering student does need to be familiar with both)
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You only find them easier because that's what you know.
I work in CAM, it's all in metric. Mm and micrometers make complete sense in my head.
It's not as if I don't use imperial or am not comfortable with them either, I just prefer metric. The 10^3 scaling is much better than 12 of these or fractions or that.
 
Squark said:
You only find them easier because that's what you know.
I work in CAM, it's all in metric. Mm and micrometers make complete sense in my head.
It's not as if I don't use imperial or am not comfortable with them either, I just prefer metric. The 10^3 scaling is much better than 12 of these or fractions or that.
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In a generations time Imperial will almost be gone when those that used it retire and the new standard is adopted by everyone. Lots of the use of Imperial is just a hang over of what people know and use. It'll die out at some point bar some really specific cases
 
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