First we have to establish that the number of protons is equivalent to the atomic number of element. Here I am assuming that you are referring to Potassium (K) - 40. Potassium, stable or unstable has 19 protons.
In physics, spacetime is any mathematical model which fuses the three dimensions of space and the one dimension of time into a single four-dimensional manifold. Spacetime diagrams can be used to visualize relativistic effects, such as why different observers perceive where and when events occur differently.
Explanation:
direction of electric field is same as that of force experienced by the test charge
Answer:
Light slows down when it moves from air into water.
Explanation:
It is the property of light that travels faster in a less dense medium.
In a more dense medium, the speed of the light slows down and bends towards the normal.
The air is less dense medium and water is a more dense medium.
When light passes from air to water, the light bends.
This is known as the refraction of light.
