CH04. Problems

CH04. Problems

Relative Motion

Textbook (9th Ed, CH04, P.75)••75 A train travels due south at 30 m/s (relative to the ground) in a rain that is blown toward the south by the wind. The path of each raindrop makes an angle of 70° with the vertical, as measured by an observer stationary on the ground. An observer on the train, however, sees the drops fall perfectly vertically. Determine the speed of the raindrops relative to the ground.

Textbook (9th Ed, CH04, P.76)••76 A light plane attains an airspeed of 500 km/h. The pilot sets out for a destination 800 km due north but discovers that the plane must be headed 20.0° east of due north to fly there directly. The plane arrives in 2.00 h. What were the (a) magnitude and (b) direction of the wind velocity?

Textbook: p82; …Old way: not easy to solve

New way: think of water motion as an added/subtracted distance

Textbook Summary

Acceleration changes direction whereThe two components changes but the Magnitude stays constant.

The y component is positive in the Lower half. Maximum at bottom Point A

Textbook summary