Please help me i need help right away

Direct current is the flow of current through a current carrying conductor in the same direction from positive to negative ends. Alternating current is the type of current our mains have where the current is constantly changing direction at a certain rate

Explanation:

Direct current  (DC) is a form of electricity that has a unidirectional flow, such that the current path in the current carrying conductor of a circuit is, at all times, in a specific single direction

Alternating Current (AC) is electricity continuously reverses its direction of flow and the magnitude of electricity at a given frequency with time. It is the of current found in electric supply cables that are found in our houses

Therefore, we have;

Direct current is the flow of current through a 1. current carrying conductor in the 2. same direction from positive to negative ends. Alternating current is the type of current our 3. mains have where the current is constantly 4. changing direction at a certain rate

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me