P-008 live motion!

A baseball will travel farther in vacuum than in air, because air friction slows it down. This appears to be a general law – a body tends to keep moving unless retarded by an outside force, and fluid drag always acts oppposite to the direction of motion.

Now, find an example where fluid drag causes an inanimate object to speed up! That is, it would have moved with constant speed if the fluid were removed, but in presence of a stationary fluid, the object speeds up.

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