Answer:
b. less than w.
Explanation:
In this question, the application of length contraction is what helps us come to our conclusion. When an object moves very fast (relative to the observer), the length of the object seems to be smaller than it actually is (again, for the observer).
This is supported by the length contraction equation below:
L = 
Here, L is the observed length
is the original length of the object
v is the relative speed between the object and the observer
and c is the speed of light
Using this equation, we can see that as the speed between the object and the observer is increased to be close to that of light, the square root in the equation gives us values less than 1.0
This effectively decreases the length that is observed.
Answer:

Explanation:
Given that there are two force of 1 pound each at right angles to each other.
The from the vector law of addition:

where:
resultant force
be the two of the forces to be added.


Answer:
330 m/s
Explanation:
The sound wave has to travel TO the cliff AND back = 2 * 49.5 = 99 m
magnitude of velocity = distance / time = 99m / .3 s = 330 m/s
Explanation:
The runner was 8.6km away from the finish line when the bird starts flying.
Therefore it takes the bird 8.6/14.4 = 0.60 hours for the bird to fly to the finish line.
In that 0.60 hours, the runner would have ran an extra 3.6km/h * 0.6h = 2.16km.
Now, the runner and the bird are flying towards each other. The distance between them is 8.6 - 2.16 = 6.44km and their combined speed is 18.0km.
Hence, they will meet in 6.44/18.0 = 0.36 hours.
Overall, the bird flew for 0.60 + 0.36 = 0.96 hours, and flew 14.4km/h * 0.96h = 13.8km.