The speed of light in a vacuum is 3.00 × 108 m/s. Enter your answer in scientific notation.

Question

a) What is its speed in km/h?

b) What is its speed in mi/min?

Answer 1

Dimensional analysis looks like a system of unit cancellation when that unit appears above (numerator) and below (denominator) the mid line (anywhere in the chain of the dimensional analysis).

So m for meter is above while s for second is below

(a) convert m to km by using the unit converter 1000 m = 1 km and make sure to place the 1000 m below the line to cancel m ... then you're left with the 1 km above the line and that's what you want to end up with km;

convert s to min then to hr using the unit converter 60 s = 1 min and 60 min = 1 hr, respectively ... since the s is below the line, make sure to place 60 s above the line to cancel s and have min above then make sure to have 60 min above the lien to can min and end with h

(b) the min below can be done just like (a);

you'll need these unit converter to go from m to mi

1 m = 100 cm 2.54 cm = 1 in 12 in = 1 ft 5280 ft = 1 mi

Keep in mind that dimensional analysis looks like a system of unit cancellation as you decide what to place above and below the line