Why does a voltmeter have infinite resistance and an ammeter, ideally with null resistance? (1 Viewer)

[Run hard@thehsc]

^^^^^^^ Year 11 content, but I did not understand it completely the first time lol!

 

[ekjchale#1]

A voltmeter measures potentiall difference and hence needs the infinite resistance if it drew current would it be able to accurately measure?
On the other hand for ammeter Ur just chucking it on one spot if that had resistance Ur blocking flow of current, so yh if that had resistance would U be able to measure current?