Finding relative velocities is a matter of finding the velocity with respect to a specific object within a frame of reference. See if you can find the relative velocities in each of these problems.
A small aircraft is moving a 26.2 m/s East. A headwind is blowing West at 14.7 m/s. What is the relative velocity of the small aircraft?
- 11.5 m/s West
- 11.5 m/s East
- 40.9 m/s West
- 40.9 m/s East
Ask yourself which is greater: the east movement or the west movement?
Excellent!
Ask yourself which is greater: the east movement or the west movement?
Ask yourself is the wind working with or against the aircraft to make the speed higher or lower?
An airplane is moving at -61.5 m/s horizontally and encounters a wind with a speed of -54.7 m/s vertically. What is the speed of the airplane relative to the ground?
- 25.9 m/s at 78.8° W of N
- 12.3 m/s at 89.9° W of N
- 43.7 m/s at 67.8° S of W
- 82.3 m/s at 41.7° S of W
Add these two velocities to get the relative velocity of the airplane with respect to the ground.
Add these two velocities to get the relative velocity of the airplane with respect to the ground.
Add these two velocities to get the relative velocity of the airplane with respect to the ground.
Great job!
An airplane is moving at a horizontal velocity of 18.8 m/s East relative to the wind. The wind is blowing the plane at 8.94 m/s at an angle of 67.5° N of E. Find the airplane's relative velocity to an observer on the ground.
- 9.86 m/s at 15.7° N of E
- 13.9 m/s at 33.8° N of E
- 23.7 m/s at 20.4° N of E
- 27.7 m/s at 67.5° N of E
You need to add these two velocities together and resolve into a resultant velocity.
You need to add these two velocities together and resolve into a resultant velocity.
Good work.
You need to add these two velocities together and resolve into a resultant velocity.
A lazy river is moving with a velocity of 0.56 m/s at an angle of 18.5° N of E relative to a stationary observer. A person riding an inner tube paddles past the observer at 1.75 m/s at an angle of 32.5° E of N. How fast and which way does the lazy river appear to go with respect to the inner tuber?
- 1.36 m/s at 72.5° S of E
- 1.36 m/s at 72.5° W of S
- 1.84 m/s at 53.3° S of E
- 1.84 m/s at 53.3° W of S
Perfect!
Find the sum of 0.56 m/s at 18.5° N of E and the opposite of the inner tuber (1.75 m/s at 32.5° W of S). You will have to resolve both into x and y components then find the sum in each direction first.
Find the sum of 0.56 m/s at 18.5° N of E and the opposite of the inner tuber (1.75 m/s at 32.5° W of S). You will have to resolve both into x and y components then find the sum in each direction first.
Find the sum of 0.56 m/s at 18.5° N of E and the opposite of the inner tuber (1.75 m/s at 32.5° W of S). You will have to resolve both into x and y components then find the sum in each direction first.
Summary
Questions answered correctly:
Questions answered incorrectly:
