Question

If you are travelling 8 knots for 45 minutes, how far will you have travelled in nautical miles?

Answer 1

Hint: Given, the speed and time. Using the formula of speed wherein speed is directly proportional to the distance travelled and inversely proportional to the time taken and substituting corresponding values, we can calculate the distance travelled in nautical miles. Knots is a unit of speed while nautical miles is a unit of distance.
Formula used:
$\text{8}\,\text{knots=8}\,\text{nautical}\,\text{miles}\,\text{h}{{\text{r}}^{\text{-1}}}$

Complete answer:
Knots is a unit for speed while nautical miles is a unit which is used to describe the distance. The relation between knots and nautical miles is given as-
$\text{8}\,\text{knots=8}\,\text{nautical}\,\text{miles}\,\text{h}{{\text{r}}^{\text{-1}}}$
Therefore, we can say that in one hour a body can cover 8 nautical miles, i.e. in 60 minutes, a body can cover 8 nautical miles, then the nautical miles covered in 1 min are-
$\dfrac{\text{8}}{\text{60}}\text{nautical}\,\text{miles=}\dfrac{\text{2}}{\text{15}}\text{nautical}\,\text{miles}$
Then the number of nautical miles covered in 45 minutes will be-
$\dfrac{\text{2}}{\text{15}}\text{ }\!\!\times\!\!\text{ 45= 6}\,\text{nautical}\,\text{miles}$
Therefore, in 45 minutes, you have travelled 6 nautical miles.

Additional Information:
The International system of unit or the SI system is a system of unit which is most commonly used around the world. It has eight fundamental units and other units can be derived from the combination of these fundamental units. Other systems of units are CGS unit, English system of units, MKS units, ESU units etc.

Note:
The SI unit for speed is $m{{s}^{-1}}$ while the SI unit for distance is metre. One nautical mile is equal to 1852 metres. The unit of nautical miles is usually used in air, marine and space travel. The units are used to represent the magnitude of scalars. Both speed and distance are scalar quantities.