Whether a EM wave is a physical body which move in up & down directions, I think just equal and opposite?
I think, in deeper sense, basis of Newton's 3rd law may be:- 1. Nature balances itself. 2. Any consicious act can cause some imbalance/disturbance to nature.(Action) 3. Nature tends to balance/correct such imbalance/disturbance to bring every imbalanced thing to its natural or balanced position.(Reaction). In some sense, it may suggest "cause and effect".
Try Lenz's Law, or the Principle of Le Chatelier. There are many effects in nature that tend to oppose change. But if you push the idea too far, you end with mystical woo, rather than science.
Look them up (Lenz's Law and Principle of Le Chatelier). They are on Wiki. I bet you won't bother, though.Please Register or Log in to view the hidden image!
Stopping a moving pendulum by applying force is an action but still it does not react equal and opoosite i.e. move again by its own.??
To stop a pendulum, something has to apply a retarding force, in the opposite direction to the direction of motion of the bob, for a time sufficient that the impulse imparted is enough to cancel its momentum. Throughout this process, the pendulum bob will exert an equal and opposite force on whatever it is that exerts this retarding force. That is what Newton's 3rd Law is telling you, in this situation. You really need to learn some basic mechanics.
I doubt if Newton's 3rd law is applicable on when anything is brought or come to its natural position. Moving Pendulum comes or brought to rest in this example which will be its natural position.
Action is not happening. Action is defined as "The state or process of acting or doing". Nature is related to happening not doing.
Kumar: It's all very well to make the statement "Nature balances itself", but that's not physics. It's far too vague and ill-defined to be physics. What kind of balance are you talking about? What is being balanced, exactly? How does this balancing occur? What you have there is a semi-mystical statement, not physics. It's a bit like when an acupuncturist talks about "balancing the Chi in the body" or "aligning the meridians" or whatever. It's all very vague and doesn't actually mean much when you dig down just a bit. Newton's 3rd law, as formulated by Newton, is really a statement that defines what Newton meant when he used the word "force". Newton's 3rd law only applies to forces. It isn't about anything else. Again, rather vague. What is being disturbed or unbalanced, exactly? How can we measure the degree of imbalance? And what is a conscious act? Can a rock cause this imbalance or disturbance you speak of, or only something like a human being? That's straying rather far from Newton's 3rd law. Newton's 3rd law often applies precisely when things are being moved out of some "balanced" position. But you haven't really defined "balance" anyway, or "disturbance" for that matter, or "natural or balanced position". You need to be far more specific before you can start doing physics. In what sense? All this is very vague.