A plane is moving due north,directly towards its destination.Its airspeed is 200 mph.A constant breeze is blowing from west to east at 30 mph.At what rate is the plane moving north?
A)198 mph
B)193 mph
C)188 mph
D)180 mph

Question

Quizplus · Accepted Answer

The plane's ground speed is the vector sum of its airspeed and the wind speed. The airspeed is 200 mph due north, and the wind speed is 30 mph due east. The vector sum of these two vectors is a vector with magnitude 200 mph and direction 19.3 degrees east of north. The rate at which the plane is moving north is the component of its ground speed in the north direction, which is 200 mph * cos(19.3 degrees) = 198 mph.

A Plane Is Moving Due North,directly Towards Its Destination