<h2>QUESTION:- </h2>
➜what is kepler's law??

Kepler gave the three laws or theorems of motion of the orbitals bodies

This law state that the celestial bodies revolves around the stars in elliptical orbit and star as a single focus.
Example :- Earth revolves around the Sun as assuming it as single focus
This also shows that earth revolves around the sun in elliptical orbit.

Area covered by the planet is equal in equal duration of time irrespective of the position of the planet.
It also states that Angular momentum is constant
As Angular momentum is constant it means areal velocity is also constant.

where:-
A is the area.
T is the time.
L is the angular momentum.
M is the mass of the body.

square of the time of the revolution is directly proportional to the cube of the distance between the planet and star in Astronomical unit.

where:-
T = time of revolution
a is the distance between the planet and star.

Your answer should be 9.7 :)
J.J. Thomson discovered the electron by noticing that a beam of particles could be influenced by an electric or magnetic force.. That is option B.
<h3>What is an electron?</h3>
An electron can be defined as the part of an atom that is negatively charged and is found revolving round the nucleus of an atom.
J.J. Thomson was the scientist that discovered electrons through subjecting two oppositely-charged electric plates around the cathode ray.
He noticed that the particles where deflected by both the magnetic and electric fields.
Learn more about cathode rays here:
brainly.com/question/4441361
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