Answer:
<em>The two balls pass each other at a height of 5.53 m</em>
<em>vf1=17.97 m/s</em>
<em>vf2=-5.96 m/s</em>
Explanation:
<u>Vertical Motion</u>
An object thrown from the ground at speed vo, is at a height y given by:

Where t is the time and 
Furthermore, an object dropped from a certain height h will fall a distance y, given by:

Thus, the height of this object above the ground is:

The question describes that ball 1 is dropped from a height of h=22 m. At the same time, ball 2 is thrown straight up with vo=12 m/s.
We want to find at what height both balls coincide. We'll do it by finding the time when it happens. We have written the equations for the height of both balls, we only have to equate them:

Simplifying:

Solving for t:

The height of ball 1 is:

H = 5.53 m
The height of ball 2 is:

y=5.53 m
As required, both heights are the same.
The speed of the first ball is:

vf1=17.97 m/s
The speed of the second ball is:

vf2=-5.96 m/s
This means the second ball is returning to the ground when both balls meet
On half life is 5370 years; 6 half lives have passed. You just multiply,
5370*6 = 32,220 years
The whistle you use to call has a frequency of 21 kHz, so you do not recognize it also because your threshold of hearing is only 20 kHz. Since you are unable to hear sounds above this value, you request your friend to blow the whistle and move farther away. The frequency will decrease due to Doppler effect.
Answer:
Please find the answer in the explanation
Explanation:
Given that a scientist conducting a field investigation records measurements of very low pressure and high relative humidity at the top of a mountain.
Since a weather map indicates that a warm front is approaching the mountain, according to the conventional current, the warm front is approaching because the weather must have been in higher relative humidity in cool air.
The warm front is approaching to replace it so that the cool air can conventionally replace the warmth air too.
The condition the scientists will most likely observe at the top of the mountain will be high relative humidity.
The answer is b
300,000 km