So may book says The direction of any magnetic induction effect is such as to oppose the cause of the effect. I have read many internet fora and posts but I could‘nt understand Lenz‘s law in simple English.And the right hand rule too. Where should I point my thumb or my fingers about to curl? Thanks
Lenz's law means that when you cause a magnetic induction effect in something, the induction effect will push away what is causing the effect. Maybe this is why motors work. The right hand rule is using your right hand, your fingers curl around the object and the thumb poiints up. Make sure you know when to use the right hand and when to use the left hand.
Lenz's Law explains the direction of induction in a magnetic material. Electromagnetic induction may occur due to changing magnetic field, changing dimensions of material or both of them. Now, in any of the above case(s), an induced e.m.f. is generated, The induced e.m.f. so produced is directed such that it opposes the effect the producing it. It can be considered to be some kind of an electrical inertia. Suppose a disk is falling through an upward non uniform magnetic field which is increasing as it goes further down. This causes induced e.m.f. in the disk. Now the direction of the induced e.m.f. will be such that it opposes the original magnetic field, i.e.- tries to decrease the external magnetic field. So, its direction will be directed downwards. Now, to find direction of current, RIGHT HAND THUMB RULE is used. It states that the curl of fingers and the thumb represent the direction of current and the direction of magnetic field produced, not respectively though. If your fingers curl along the current, the thumb will point along the field, and vice versa. It's upto you to decide whichever is suitable. This rule thus proves that Current and Induced magnetic field are normal to each other. In the above example, the current flow will be CLOCKWISE.
