HEADWINDS and TAILWINDS • The direction of a headwind is into the frontof the plane. • So a headwind the will cause the plane to slow down.
A tailwind blows from behind the plane. It blows into the back, or tail, of the plane. • This would cause the plane to speed up.
A plane is flying at 100 m/s when it experiences a tailwind of 15 m/s. What is the resultant speed? • The plane’s resultant speed is 115 m/s.
A boy is riding his bike at 5 m/s when a gust of wind blows directly toward him at 2 m/s. • Is this a headwind or a tailwind? • What is his resultant speed?
Vectors and Scalars • A vector is a quantity that has both magnitude and direction. • Magnitude is a number or amount.
A car has a velocity of 25 m/s north. What is the magnitude of its velocity? • 25 m/s
Speed does not have direction. It has only magnitude. • So speed is not a vector.
A scalar is a quantity that has only magnitude. • Time does not have direction. It is a . • Acceleration does have direction. It is a .
Mass has magnitude but not direction. • It is a . • Weight has magnitude but not direction. • It is also a .