Using Newton’s first law of physics, which explains why it is harder to swim in water with a current (like the ocean) than in contained water (like a pool)?
A.
Perpetual motion can only be interrupted by an unbalanced force.
B.
The current will interfere with perpetual motion more than still water.
C.
It takes much more strength to swim if there is a current than in a pool.
D.
Still water is an immovable object, but currents have their own momentum.