Question

An airplane flies at 120km/h relative to air. There is a wind blowing at 90km/h relative to the ground. Calculate the speed of the airplane relative to the ground if.

a) they have opposite direction
b) perpendicular.​

Answer 1

Step-by-step explanation:

a) if theya re OPPOSITE then the wind speed subtracts from the airplane's speed ( a headwind) sooooo 120 - 90 = 30 km/hr

b) if the two speeds are perpendicular , you can use Pythagorean theorem:

R^2 = 120^2 + 90^2

R = 150 km/hr