Not to strong (because don't chech second string but it easy to settle) and can be is not posix compilant but very simple:

sed '/^Some text/{:1;/another thing$/!{N;b 1}
     s/.*/this is completely\ndifferent text/g}' input.txt


First command add lines from Some text until have met another thing then second line change it to other text.

NOTE Limitation is that Some text should always be followed by another thing.

Replace multiline string in files
According to Ohm's law, V=IR (voltage equals current times resistance).

So if the voltage increases, then the current increases provided that the resistance remains constant.

I know that Voltage or potential difference means work done per unit positive charge in bringing that charge from one point to another.

So according to Ohm's law, if the work done per unit charge increases then current will increase. How can this be true? Point out my mistakes.
