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3 years ago
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Easton Johns
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I like to use Dimensional Analysis for these types of questions.
In a nutshell, we use fraction cancelling using coonversions for each unit.
Let's convert 27 km/h to m/s
(27 km/1 hr)(1000 m/1 km)(1 hr/3600 s) = 27,000 m/3600 s = 7.5 m/s
Notice how the km cancel and the hr cancel
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Click here to view my profile and arrange a free introduction.To convert from km/hr to m/s, first convert from km to m by multiplying by 1000 because 1km = 1000m. Then you need to divide by 60 to get metres per minute and then divide again by 60 to get metres per second.
The formula to convert km/h to m/s is simple to understand. First, let us convert kilometer to meters and hours to seconds, individually. We know that 1 kilometer = 1000 meters and 1 hour = 3600 seconds. Now, 1 km/h can also be written as 1000/3600: 1 (kilometer/hour) = 1000/3600 (meters/seconds). So, this is the formula which is used to convert km/h to m/s. On simplifying 1000/3600 further, we get 5/18, which can also be used as the conversion factor.
Now, it is possible to convert km/h to m/s using the above formula. We multiply the given speed (in km/h) with the fraction 1000/3600, to get the speed in m/s. We can also use its simplified form (5/18) as the conversion factor.
For example, 10km/h
10km —>10 000m
10 000m/h
There are 3600 seconds in a minute
Therefore, 10 000/3600=2.778
10km/h —> 2.778m/s
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