Why did the apple stop in the middle of the road?

This joke gets its giggle power from a classic bit of wordplay, specifically a pun on the word "juice." Your brain expects "juice" in the context of an apple to mean the delicious liquid inside the fruit (Review). The punchline, however, cleverly swerves into the other, less literal meaning, suggesting the apple somehow needed fuel or power, much like a car running on gasoline or an electronic device needing a charge.

Apples, of course, are famous for their sweet, pulpy "juice," whether you're biting into a crisp one or sipping a glass of the bottled kind. But the phrase "ran out of juice" is also a common idiom we use when something loses its power – think a phone battery dying or a car sputtering to a halt. The humor comes from the delightful absurdity of applying a vehicle's predicament to a piece of fruit, all thanks to that one versatile word and its double meaning.