Why do I measure voltage on a breaker that’s off?

My breaker #1 (115VAC) is connected to my dishwasher. My breaker #2 (115VAC) is connected to my garbage disposal.

Why do I get 38.5VAC on the dishwasher line, even when breaker #1 is off? When breaker #2 (Garbage Disposal) is also off, I get 0 VAC on dishwasher. Why?