You want to design a spy bracelet that can send a signal to a friend's bracelet when you are nearby. which type of electromagnetic radiation would your design use?

If you are going to design a spy bracelet that can send a signal to your friend's bracelet that is nearby, the best and suitable type of electromagnetic radiation to use is the radio waves. The radio waves are used in order to have a remote sensing. Radio waves has the ability to send or transmit with the use of TV (broadcast), hand phone and even radio. This is the type of radiation that is best to use when you are trying to send a signal.