A1: In practice, the USB specification limits the length of a cable between full speed devices to 5 meters (a little under 16 feet 5 inches). For a low speed device the limit is 3 meters (9 feet 10 inches). Q2: Why can't I use a cable longer than 3 or 5m?
Clouds form when moist, warm rising air cools and expands in the atmosphere. The water vapor in the air condenses to form tiny water droplets which are the basis of clouds.
Clouds form when the air is saturated and cannot hold any more water vapour, this can happen in two ways: 1  The amount of water in the air has increased - for example through evaporation - to the point that the air cannot hold any more water.