Radio activated relay

I would like to design a radio controlled activated relay. When I press a button it will trigger the relay and it will cause circuit breakers to trip since I short the other two ends. My relay needs atleast 6V for the relay to be triggered. Can I use a remote controlled car (rated with two AA batteries but I modified to a 9V battery) to activate he relay by placing the two contacts at the motor connector to the relay so that when I press the Go button it will be activated.

Just try it, if the relay coil takes less power than the motor it should work.
Warning: using relay contacts to cause a short circuit is *not* a good idea. You mention circuit breakers tripping, I guess you mean MAINS circuit breakers. If so, you will see your relay contacts vaporise instantly and perhaps start a fire - take care!

Wha? a relay is an automated switch... since when does a switch "vaporize".. as long as its rated high enough hes all set.
the hardest part of that circuit is the transmitter/ receiver part.... id like to see what hes using .. that and the latching part of the circuit.

Jaw, read the original message again. The way I read it he wants to create a short circuit by remote control. Now, if you do that with mains power you need mighty big relay contacts or a very fast fuse/circuit breaker to safe the relay contacts for another go.
There could be several hundreds of amps for a tiny instant across the contacts.
If I wanted to do that remote control power switch off trick I would fit an ELCB (earth leakage circuit breaker) and then remotely short the life wire to earth. The ELCB trips instantly with no big current across the relay contacts, just 50mA or so.

Now, kevinloh, tell us what you *really* want to do

I'm just tryin to see how fast the circuit breakers trips the circuit. So, Can I use the contacts one is for live and one is for ground?