When the total product starts falling, then the marginal product is

In the context of production, the Total Product (TP) refers to the total quantity of output produced by a firm. The Marginal Product (MP) is the additional output obtained by employing one more unit of a specific input, while keeping all other inputs constant.

When the Total Product starts to fall, it indicates that each additional unit of input is contributing less and less to the total output, to the extent that the output is actually decreasing. This means that any added input is no longer producing additional output but instead reducing it. Therefore, the Marginal Product in this situation is actually negative.

Here is why:

• Consider the scenario where adding extra workers or resources does not increase output, and might even disrupt production.
• At this point, the contribution of added input becomes detrimental, causing a decline in the total output.
• Thus, the Marginal Product turns negative, because the next unit of input is not just unproductive, it makes the overall production lower than before.