a current there is a deep ocean current wich is in the midnight zone of the ocean. but there is also a surface current witch is in the sunlight zone of the sea.
This can either be a wave or pendulum in which a motion of energy or a body repeats a constant motion usually up and down/side to side.
Back and forth in the direction of propagation of the sound waves.
it's called frequency. it can go up and down or back and forth
turning back and forth down the slope
vibration
it is a vibration :)
vibration
vibration
Could be a bad switch Could be a broken cable
The US and North Vietnam. US jets bombed the north; the north shot them down. (Back and forth; back and forth).
Yes.
Yes.