Final answer:
While eating four pounds of food may temporarily increase what you see on the scale, it is unlikely to result in a four-pound weight gain the next morning, due to the body's metabolism, usage of calories, and excretion processes. Over time, consistent overeating will lead to weight gain. Scales measure weight but are calibrated to display mass, which doesn't change with location.
Step-by-step explanation:
The main answer to whether you would weigh four pounds more the next morning after eating four pounds of food during the day is not as straightforward as it seems. While immediately after eating, the scale may indeed reflect an increase in weight equivalent to the weight of the food consumed, this will not be the case the next morning. Your body is constantly at work metabolizing, digesting, and using energy, which means that part of the food intake will be converted into energy, some will be stored as fat if you consume more calories than you burn, and some will be eliminated as waste.
One pound of body fat contains about 4,000 calories, so to gain one pound of fat, you would need to consume 4,000 calories more than you expend. Over the course of a day, your body will likely use some of the calories for energy and remove some through excretion, so it's unlikely you'll see a direct four-pound increase on the scale the next morning. However, if you consistently consume more calories than you burn, over time you will see an increase in weight.
Furthermore, the concept of weight versus mass is relevant here; bathroom scales measure your weight, which is the force due to gravity and is expressed in newtons (or pounds). Most scales are calibrated to display mass, which is constant regardless of location but the weight can change depending on the gravitational pull. For example, on the Moon, you would weigh less but your mass would remain the same.