Physical address of a computer

Logical
address and physical address: How to find 

or get a physical address of a RAM


physical address of computer or operating system

All the c variables are stored in the residence memory.

In turbo C 3.0, 20 bits address of the memory cell is
known as physical address or real address. In 20 bits,
we can represent address   from 0x00000 to 0xFFFFF. That
is all c variables must have