Explanation:
First, we will calculate the electric potential energy of two charges at a distance R as follows.
R = 2r
= 
= 0.2 m
where, R = separation between center's of both Q's. Hence, the potential energy will be calculated as follows.
U = 
= 
= 0.081 J
As, both the charges are coming towards each other with the same energy so there will occur equal sharing of electric potential energy between these two charges.
Therefore, when these charges touch each other then they used to posses maximum kinetic energy, that is,
.
Hence, K.E = 
= 
= 0.0405 J
Now, we will calculate the speed of balls as follows.
V = 
= 
= 0.142 m/s
Therefore, we can conclude that final speed of one of the balls is 0.142 m/s.
Answer:

Explanation:
Tarzan swing can be thought of as change in potential energy by going from higher location We solve for height of beginning of the swing by using simple cosine equation:
So

ΔE=mg(h₂-h₁)

The potential energy of Tarzan initial position is converted into kinetic energy of his swing.By using kinetic equation
Answer:
The boundaries cause the waves to change direction an effect called <u>refraction.</u>
Explanation:
When a wave crosses a boundary between different materials, the speed of the wave and its wavelength changes.When passing from air to water the two properties (speed and wavelength) decreases, and the wave is observed to change direction as it crosses the boundary between the two material.The bending of the wave is called refraction.
Kinetic energy is formed when the object is in motion.
Potential energy is the energy that is formed relative to others.
One of the example is Corn flour factory.
Corn turned into flour by a windmill that moved by the waterfall. Movement of the mill is relative to the power given by waterfall (potential energy) and the spinning crushes the corn into flour (kinetic energy)