Change Unit (Measure)
How to change the unit of measurement: 3 examples and their solutions.
Examplem → cm
First write (3 m).
To remove the unit [meters],
you need [meter] in the denominator.
And you need the unit [centimeters] in the numerator.
1 m = 100 cm
So multiply [100 cm]/[1 m].
Cancel the [meter(s)] units.
(3)⋅(100 cm)/1 = 300 cm
So 300 cm is the answer.
Examplehour → second
First write (2 hr).
To remove the unit [hours],
you need [hour] in the denominator.
And you need the unit [seconds] in the numerator.
1 hr = 60 min
This doesn't show [seconds].
But use this to remove [hours] first.
So multiply [60 min]/[1 hr].
Next, to remove the unit [minutes],
you need [minutes] in the denominator.
And you still need the unit [seconds] in the numerator.
1 min = 60 sec
Use this to remove [minutes] and write [seconds].
So multiply [60 sec]/[1 min].
Cancel the [hour(s)] units.
And cancel the [minute(s)] units.
(2)⋅(60/1)⋅(60 sec)/1 = 7200 sec
So 7200 sec is the answer.
Examplekm/h → m/s
36km/h means 36km per 1 hour.
So write (36 km)/(1 hr).
First, remove the unit [kilometers].
You need [kilometer] in the denominator.
And you need the unit [meter] in the numerator.
1 km = 1000 m
So multiply [1000 m]/[1 km].
Next, remove the unit [hours].
you need [hour] in the numerator.
And you need the unit [seconds] in the denominator.
1 hr = 60 min
This doesn't show [seconds].
But use this to remove [hours].
So multiply [1 hr]/[60 min].
To remove the unit [minutes],
you need [minutes] in the numerator.
And you still need the unit [seconds] in the denominator.
1 min = 60 sec
Use this to remove [minutes] and write [seconds].
So multiply [1 min]/[60 sec].
Solve these ratios by cancelling.
Cancel the [kilometer(s)] units.
Cancel the [hour(s)] units.
And cancel the [minute(s)] units.
(36/1)⋅(1000 m / 1)⋅(1/60)⋅(1/60 sec)
= (10 m)/(1 sec)
= 10 m/s
So 10m/s is the answer.