Riverboat and Airplane Problems

Which statement describes a vector?

• It has magnitude but no direction
• It has direction but no magnitude
• It has both direction and magnitude
• It has constant magnitude but no
   direction

Observers using different ___________________ may measure different velocities for an object in motion

• frame of reference

• relatives of motion

• projectile motions

• constant velocity

All motion is described as relative because

• how do you ever really know if something is in motion
• motion means different things to different people
• everything in the universe is constantly in motion, so it depends on your frame of reference

A motorboat, which has a speed of 5 m/s in still water, is crossing a river (from west to east) The river's current is flowing south at 3.3 m/s. What is the magnitude of the boat’s resultant velocity with respect to the starting point?

• 3.3 m/s

• 5.0 m/s

• 6.0 m/s

• 8.3 m/s

A motorboat, which has a speed of 5 m/s in still water, is crossing a river (from west to east) The river's current is flowing south at 3.3 m/s. At what angle downstream is the boat travelling?

• 33 degrees

• 41 degrees

• 49 degrees

• 0.66 degrees

Tags

NGSS.HS-PS2-1

A motorboat, which has a speed of 5 m/s in still water, is crossing a river (from west to east) The river's current is flowing south at 3.3 m/s. The distance from shore to shore is 20 meters. How long will it take the boat to cross the river?

• 6.1 seconds

• 4 seconds

• 0.25 seconds

• 0.17 seconds

A motorboat, which has a speed of 5 m/s in still water, is crossing a river (from west to east) The river's current is flowing south at 3.3 m/s. The distance from shore to shore is 20 meters. How far downstream will the boat land?

• 20.0 m

• 13.2 m

• 30.3 m

• 10.0 m

Tags

NGSS.HS-PS2-1

A motorboat, which has a speed of 5 m/s in still water, is crossing a river (from west to east) The river's current is flowing south at 3.3 m/s. At what angle upstream should the boat aim in order to go straight across the river?

• 0.66 degrees

• 48.7 degrees

• 33.4 degrees

• 41.2 degrees

The president’s airplane, Air Force One, flies at 250 m/s to the east with respect to the air. The air is moving at 35 m/s to the north with respect to the ground. Find the velocity of Air Force One with respect to the ground.

• 252 m/s
• 222 m/s
• 435 m/s
• 125 m/s

The president’s airplane, Air Force One, flies at 250 m/s to the east with respect to the air. The air is moving at 35 m/s to the north with respect to the ground. What is the angle and direction of the plane's motion above the ground?

• 7.97 degrees North of West

• 7.97 degrees West of North

• 82.03 degrees North of West

• 45 degrees Northwestern