If Earth was twice as far from the sun, the force of gravity attracting the Earth to the sun would be only one-quarter as strong. The correct answer will be C.
Answer:
when the ground is very hot and the air is cool.
Explanation:
The hot earth warms a layer of air right above the ground. Light is refracted as it passes through the cool air and onto the hot air sheet (bent). A coating of very warm air near the earth bends the light from the sky almost into a U-shaped bend.
Answer:
The value is 
Explanation:
From the question we are told that
The value of charge on each three point charge is

The length of the sides of the equilateral triangle is 
Generally the total potential energy is mathematically represented as
![U = k * [ \frac{q_1 * q_2}{r} + \frac{q_2 * q_3}{r} + \frac{q_3 * q_1}{r} ]](https://tex.z-dn.net/?f=U%20%20%3D%20k%20%2A%20%20%5B%20%5Cfrac%7Bq_1%20%2A%20%20q_2%7D%7Br%7D%20%20%2B%20%20%5Cfrac%7Bq_2%20%2A%20%20q_3%7D%7Br%7D%20%20%20%2B%20%5Cfrac%7Bq_3%20%2A%20%20q_1%7D%7Br%7D%20%5D)
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Here k is coulomb constant with value 
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Wave reflection occurs when waves reflect or rebound off of a surface. This is like an echo because the sound waves are reflected from a distant surface
Answer:
B. learning happens through experience and practice.