For instance, creating loud noises, fighting, challenging people to fight, disturbing others by making loud and unreasonable noises (this includes play music loudly), or using foul language with the intent to solicit violence are all acts that can be construed as disturbing the peace.
The most common max power on a new radio is 100 watts, although some of the more expensive radios could have more. With the stock 100 watt radio, depending on atmospheric conditions, your antenna type, and the height of your antenna, you could talk to most all countries, but not on demand. What I mean by demand is that you can't control when you will make each contact, but each day, or night, you may contact some part of the world.
Using speakers with average sensitivity, a rock band playing in a medium-sized club will need around 1,500 watts total power at a minimum, whereas a pop or jazz group might need between 250-750 watts. For simple folk music in the same venue, that requirement can come down to as little as 60 watts.