The centripetal force needed to keep earth in orbit is gravity.
Exert force upward.
Like when you pick something up from the floor, or walk up the stairs.
A light wave that hits the surface of a pool gets refracted and gives us an apparent image of the surface of the pool, following the concepts of refraction.
<u>Explanation:</u>
Let’s recall the concept of refraction when a light wave passes from medium of rarer to denser. There is a change in the speed of light while travelling from medium of rarer to denser.
There can be a change in the direction as well. This property is known as “Refraction” and the best example to see refraction is watching the surface of a clean pond, lake or pool.
When the light travels from a rarer medium (air) to a denser medium (water), it changes its angle of direction and gets refracted and hit to our eye lenses. With this, we see the surface of the pool at a changed angle and it seems to be a bit shallow than its original depth.
Scientists think the solar system formed around 4.6 billion years ago from a cloud of dust and gas known as a solar nebula. Gravity collapsed the material on itself as it began to spin. This formed the sun in the middle. The planets formed when rock joined together in clumps and became bigger and bigger. And thus, our solar system was formed. Hope this helped
They surface at night to eat leaves off the ground.