A current that runs parallel to the shoreline is called a rip tide or rip current.
rip tide
rip current.
Rip current
a rip current
rip current.
No, you should NOT try to you swim against a rip current or rip tide. You will NOT usually make it back to shore. Instead, you should swim perpendicular to the rip. It will carry you down shore, but you'll get to shore safely.
Undertow.
? rip current ?
Swim parallel to the ocean shore until clear of the current
Faster movement creates more vibrations in the paper and in turn a higher frequency (pitch)
Rip current