Answer:

Explanation:
As we know that the displacement of the particle from the mean position is 1/5 times of its amplitude
so we have


so now we have

now we have

so the phase other particle in opposite direction is given as

so we have phase difference given as


Answer:
Its mechanical energy is the same.
Explanation:
If forces are only conservative, the mechanical energy will be the same.
It can be different if energy get transformed in another kind of energy like elastic energy for example, although the amount of energy is always the same.
If we just have mechanical energy not geting transformed we have:
Em=K+U
Em: Mechanical energy
K: Kinetic energý
U: Potential energy
Then if Kinetic energy decreases 10J, Potential energy will grow up 10J to keep the same amount of mechanical energy.
Answer:
the answer would be microwelds.
You are correct earth science is studied to predict planetery changes