If install SQL-Server in other computer then data send/receive time can be slow?

I don't want to install SQL-server and Web-Server in same computer, so I want to install web-server in computer "A", and SQL-server in computer "B"..

My questions are below :

1) Should I use an external("B") SQL-server to run a Web-application("A"), or is this bad way ??

2) Can take this process some extra time to send/receive data between Web-server("A") and SQL-server("B") ??

3) Is it complex to configure ??

I don't have knowledge on this topic, so please help me..

Thanks..