Question

An aeroplane leaves an airport and flies due north at a speed of 1,000 km per hour. At the same time, another aeroplane leaves the same airport and flies due west at a speed of 1,200 km per hour. How far apart will be the two planes after `1 1/2` hours?

Answer 1

Distance travelled by the plane flying towards north in `1 1/2 `

Similarly, distance travelled by the plane flying towards west in `1 1/2 `

Let these distances be represented by OA and OB respectively.

Applying Pythagoras theorem,

Distance between these planes after `1 1/2 `

`= (sqrt((1500)^2 + (1800)^2)) `

`= (sqrt5490000)`

Therefore, the distance between these planes will be `300sqrt(61) `