Tracking units is important. Not just conversions either, but the resulting unit as well. Like if you have 40 m/s and you multiply by 5s, your resulting unit is ms/s where seconds cancel out and results in m. If the answer wasn’t supposed to be distance, you know you screwed up.
Jester471 on
God, I had an orbital mechanics test where we were given the departure and arrival date of a probe sent to mars and we had to determine if it’s was using an optimal hohmann transfer. At the time that question was easy enough. But I wasted SO much time without a calendar trying to make sure I counted the days right to give the yes/no answer at the end. It was only a few minutes but minutes were precious on those tests. Can’t you just say it’s going to take X days instead of me trying to back into that?
jommakanmamak on
We use km/h in our daily lives
I know how fast 100km/h is
But I have no idea how fast 100m/s is
[deleted] on
[deleted]
SizeableFowl on
Just multiply by 1.
x(m/s) x (1 km/1000 m) x (3600 s/1 hr) = y (km/hr)
1km =1000m so multiplying by 1 km/ 1000 m is the same as multiplying by 1/1, the units cancel so you end up with km/s
3600 seconds =60 minutes 1hr and when you cancel those units you end up with km/hr.
nsfvvvv on
Why not just footballfields / hamburgers.
PlayedKey on
Seems like it’s more to check you’re actually reading questions carefully. Details matter in a lot of things.
ChuckBorris_1st on
no way in hell id use km/h. You’ll know when you understand physics for real.
25 Comments
It’s called “promoting logical thinking” and handling multigstep tasks..
I’ve seen this meme for at least 5 times
Magic 3,6
I’ve had this happen quite a few times.
As it turned out, the teacher didn’t read the questions. The answer would have been for using m/s either way…
it could be in football field/fortnight
It’s 4 whole button presses on a calculator
×3.6 for m/s to km/h, divide for vice versa
6 knots is 3m/s. Roughly. It’s an easy way to estimate a boat’s speed as it goes past a fixed object.
Half the exam is just surviving the units
Be thankful they aren’t using imperial lol
Km/h is a common measurement used. Think of driving.
Also the conversion is extremely easy.
It what you will have to do in real life too
Newsflash, real world physics problems are rarely in the “convenient for you” units because they were measured in “convenient for someone else” units.
Basically any math problem even in grad school
This is pretty basic math, get good noob.
Teacher: just small change 😅
Me: lost in math forever 😂
Now I am still converting… send help 😆
At least for this I’m glad that as a European I don’t need to learn about miles
If they don’t their students will [not understand the difference between 0.002$ and 0.002 cent](https://www.reddit.com/r/theydidntdothemath/comments/9byhvi/verizon_doesnt_understand_the_difference_between)
Tracking units is important. Not just conversions either, but the resulting unit as well. Like if you have 40 m/s and you multiply by 5s, your resulting unit is ms/s where seconds cancel out and results in m. If the answer wasn’t supposed to be distance, you know you screwed up.
God, I had an orbital mechanics test where we were given the departure and arrival date of a probe sent to mars and we had to determine if it’s was using an optimal hohmann transfer. At the time that question was easy enough. But I wasted SO much time without a calendar trying to make sure I counted the days right to give the yes/no answer at the end. It was only a few minutes but minutes were precious on those tests. Can’t you just say it’s going to take X days instead of me trying to back into that?
We use km/h in our daily lives
I know how fast 100km/h is
But I have no idea how fast 100m/s is
[deleted]
Just multiply by 1.
x(m/s) x (1 km/1000 m) x (3600 s/1 hr) = y (km/hr)
1km =1000m so multiplying by 1 km/ 1000 m is the same as multiplying by 1/1, the units cancel so you end up with km/s
3600 seconds =60 minutes 1hr and when you cancel those units you end up with km/hr.
Why not just footballfields / hamburgers.
Seems like it’s more to check you’re actually reading questions carefully. Details matter in a lot of things.
no way in hell id use km/h. You’ll know when you understand physics for real.