Hi,
Thank you everybody for this very active conversation.
I stopped at the conclusion that:
1. current is limited by resistor to the value described by the Ohm's Law
I'm not sure I care for the idea that current is limited unless you add 'for a given voltage'. The resistor drops a voltage based on the current flowing through the resistor, nothing more, nothing less. The resistor itself may not be the only component in a circuit and, therefore, other components impact the current flow.
I don't think I would use the term limit. The resistor simply doesn't do that all by itself. Think a little harder about E=I*R and the other permutations: R=E/I or I=E/R
2. but, current above the limit of resistor will be changed into heat
No! Every single bit of voltage dropped across the resistor is turned to heat. If you want to think in current, every ampere through the resistor causes heat. P=I*E, P=E
2/R, P=I
2R. P is in Watts, E is in Volts, I is in Amps and R is in Ohms.
There's no such thing as a limit. You are adding a discontinuity or asymptote (a limit, some kind of flattening in the graph of current versus voltage) to a linear relationship. There simply isn't some magic 'limit'. Ohm's Law is a linear, continuous function for all practical purposes.
E=I*R for all reasonable values of the variables. Obviously there are other design considerations like flash-over voltage and maximum allowable dissipation. That's why there are resistors with different dissipation ratings. 1/8W, 1/4W, 1/2W...100W and so on.
3. I do not understand why if current over limit is changed into heat then why "battery" life is different for each resistor from my example ( and I know "because different current" - I am talking about heat generated).
4. To understand p3 above, I need to read on material conductivity and how Ohm's Law was formulated.
The battery is NOT a perfect source. If it is rated, say, 1 Ah, that doesn't mean that it can provide 3600 Amps for 1 second. 1 hour = 3600 seconds. There is a very non-linear graph of output current versus depletion time. If you take the current out at a high value, the charge life will be a lot shorter and the Ah number doesn't apply. Usually the rate is given for some current and/or some time. It might actually be capable of providing 0.1A for 10 hours.
Read the second paragraph here:
https://www.allaboutcircuits.com/textbook/direct-current/chpt-11/battery-ratings/