An increase in aggregate demand will always lead to a decrease in nominal interest rates, due to a direct relationship between these two factors.

An increase in aggregate demand means that people and businesses are buying more goods and services in the economy. When this happens, companies may need to borrow money to expand their production to meet the higher demand. As a result, the increased borrowing can lead to a higher demand for loans, which might actually push interest rates up instead of down. It's important to note that while there can be some short-term effects where demand might initially lower interest rates, the overall relationship is more complex. For example, if a lot of people suddenly want to buy cars, car manufacturers might borrow more money to produce more, which could eventually lead to higher interest rates due to increased demand for loans.