First, he destroys a hot dog with 1,000 joules of energy. But that amount of energy doesn’t do much damage against a watermelon. Which is why the Backyard Scientist brings out the big guns—a capacitor that is capable of sending out 20,000 joules.
How much is that? The equivalent of shooting off four .50 caliber sniper rifles at the exact same time, or as he writes in the YouTube description, “this is basically like what would happen if a lightning bolt struck a watermelon.”
While the watermelon is the main course, also check out what happens when a steak is cooked with the same amount of energy. It’s, um, electrifying.