I want to do this with the "Unit Conversion" method. A vehicle is traveling 15 kmh, how long does it take to go 100 meters in seconds. (I know 15000x=3600(100) x=24s....that's not the question)
I want to know how to do it with "Unit Conversion" method where all the unwanted units cancel out.
i.e.
15km/hr *1000m/Km *hr/3600s ...
I need to set up the fractions in such a way to end up with 100m/24s without having to do anything else. Maybe 100 meters needs to be paired with something else?
2007-08-30 14:56:51 · 3 answers · asked by RogerDodger 1 in Science & Mathematics ➔ Physics
I could end up with 100m/24s OR 24s/100m; either way, it doesn't matter.
2007-08-30 14:58:35 · update #1
I just answered my own question, maybe you guys are curious:
(100m/1)*(1km/1000m)*(1hr/15km)*(3600s/hr)= 24s
It has something to do with putting what you start with (100m) in the top left
2007-08-30 15:13:43 · update #2
(100m/1) * (1km/1000m) * (1hr/15km) * (3600s/1hr) = 24s
2007-08-30 15:15:13 · update #3
It can only be done in two operations.
1...Find metres per second (m/s)
(km/hr x 1,000 m/km) / 3,600s/hr
= m/s. ('km' and 'hr' cancel)
2...m / m/s = s. ('m' cancel)
Your question..
1...(15 km/h x 1,000m/km) / 3,600s/hr
= 4.17m/s ('km' & 'hr'cancel).
2...100m / 4.17m/s = 24s ('m' cancel)
2007-08-30 15:28:45 · answer #1 · answered by Norrie 7 · 0⤊ 0⤋
(15km/1hr) * (1hr/3600s) * (1000m/1km) = ?
The units of kilometer and hour should cancel out and give you the vehicle's velocity in metes per second. To get your answer for the time it takes to go 100meters, just divide the above answer by 100m and the only unit that should be left is seconds. You just have to calculate the numbes now.
2007-08-30 22:05:49 · answer #2 · answered by Toledo Engineer 6 · 0⤊ 0⤋
You're already there:
15km/hr * 1000m/km * 1hr/3600s
= 15000 m / 3600 s
Divide top and bottom by 150:
= 100m / 24s.
2007-08-30 22:01:22 · answer #3 · answered by Scarlet Manuka 7 · 0⤊ 0⤋