A tennis serve is out if it hits the green without hitting the main court, or if it hits the net
Because a serve hits the net.
Do you mean "let"? If so, a let is when a serve touches/nicks the net AND lands in on a player's serve. People call "let" so the server knows their serve hit the net. If a server hits a let, they get to redo their serve.
a serve that you cant get back over the net e.g. its to powerful or you cant get to it in time
A net ball means that when a player hits their serve and it hits the net, then bounces in. That is when a net ball is called.
Yes
A player serves and the ball hits the net, then jumps into the serve field on the other side of the net. The player gets to repeat the service until it's either a good serve or a double-fault.
There are no 'faults' in tabletennis. If you miss the first serve, you lose the point. However, having said that, if you serve a "let" - where the ball plays truly on each side of the net, but touches the net in its travels across the net, you are permitted to retake your serve to make it a 'clean' serve that does not touch the net.
Let is from the word filet, a French word for the net. In tennis, it is a type of serve that is not valid and has to be done again.
The opposition get a point for a double fault
If it hits the net and goes into the service box, you get one re-serve (as opposed to getting two re-serves if you do that on your first serve). If it hits the net and does not land in the service box, then it is a double fault.
In tennis, a service is when one opponent hits the tennis ball over the net into the opposite box. It's how tennis players start the point. If you miss the first serve, you get to serve again, but if you miss that, the point is over. Your opponent won that point. If the ball hits the net before bouncing over, it is called a let. Source: Many years of playing tennis.