Watermelon trivia:Why do you know that it is mature when you pat it with your hand?

Studies have shown that it is scientifically based on tapping watermelon with hand and listening to sound to judge the quality of watermelon.

The test principle of this method is that the propagation of sound waves in the medium is affected by the density and texture of the medium, so it is possible to judge the quality of the watermelon by listening to the sound.