If you are asking for a proof on having at least 3 dimensions in space, you can find the physical proof anywhere in your daily life activities. Just the fact that solids have volumes is a proof already that we live in a three-dimensional space. We can move forwards, backwards, sidewards and in all other directions possible.
When you go right into detail, the fundamental laws governing these proofs are very technical. They have differential equations to show as proof. It is too detailed to discuss here. The important things is that, these fundamental laws are what explains the science in our basic activities and natural phenomena:
*Gravitation and planetary motion
* Translation, rotation, magnetic field, forces
* Integrals of equations:
Answer:
E=-1.51 eV.

Explanation:
The nth level energy of a hydrogen atom is defined by the formula,

Given in the question, the hydrogen atom is in the 3p state.
Then energy of n=3 state is,

Therefore, energy of the hydrogen atom in the 3p state is -1.51 eV.
Now, the value of L can be calculated as,

For 3p state, l=1

Therefore, the value of L of a hydrogen atom in 3p state is
.
Answer:
Explanation:
the light ray leaving a medium in contrast to the entering or incident ray.