who is Walter Lewin?

Is this guy a freak?
No way...He's such a brilliant teacher that I always rued why didn't I go to MIT ..tch tch!!
but no worries I can still watch him in action and I wondered where does he bring in so much energy and how many teachers in my life had so much fun while teaching physics. I think no one!
Demonstrative physics is his forte and de does this with great success ....many tradition follower might say what a waste of energy but this is the best way to get the ideas across to students.
I would ask all the kids and young aspirants to watch his lecture not to score more in exams but to know what is the essence of physics and science in general.He had shown 600 demonstration in about 100 lectures  even risking to hurt himself.
The energy, the enthusiasm he exudes is unmatched and I enjoy his lectures and I learn a lot even now even when i get little time to indulge after my regular Software job.
I do it  because Physics  is fun.
After doing a dangerous demonstration, Lewin says "Physics works and I m still alive" !!
Lewin is a maverick!

law of motion

How many laws of motion are there that Newton put it down?
u say 3?
and which says what?
I don't remember but all you need to know is Mass times acceleration gives  the force.
in short, F=ma
this one single equation means the whole world to a physicist.
how simple is that ?
F=ma and it tells great deal of things.
it says that u can calculate the second derivative of the position that is acceleration, given that mass and force on the system of a particle under consideration is known.
F=md/dt (x^2)

Classical mechanics involves Newtonian physics.
The important consideration is frame of reference and by that we mean here Inertial frame of reference.
since law of physics(eg Newton's law) is invariant in all inertial frame of references so we have choices to make in selection of frame of reference.