Question

1. An airplane heads due west at a speed 150 km/h relative to the wind. If the wind is moving

   at 30 km/h toward the north, what is the speed of the airplane relative to the ground?

2. A jet airliner moving initially at 300 mi/h due east enters a region where the wind is blowing at

   100 mi/h in a direction 30◦ north of east. What is the speed of the aircraft relative to the ground?

3. A certain river is 0.5 mi wide, and flows due east at 2.7 mi/h relative to the shore. A boat

   attempts to cross the river straight from one shore to the other. If the boat travels due north at 1.7 mi/h relative to the river,

   (a) what is the speed of the boat relative to the shore?

   (b) how far downstream is the boat when it reaches the opposite shore?

4. How long does it take an automobile traveling in the left lane at 60 km/h to become even with

   another car that is traveling in the right lane at 40 km/h when the car’s front bumpers are

   initially 100 m apart?

10. A storm spins in a given direction because of what? Pick one choice from below.

(a) Its velocity
(b) Its energy
(c) Its location in northern hemisphere or southern hemisphere (d) All of the above

Answer 1