Final answer:
The impact of population growth on capital deepening illustrates the principle of diminishing returns to capital in economics.
Step-by-step explanation:
The impact of population growth on capital deepening is an illustration of the principle of diminishing returns to capital in economics. Capital deepening refers to increasing the amount of physical and human capital per worker. However, as the population grows and the amount of capital per worker decreases, the additional investment in capital leads to diminishing returns, as the increase in output becomes smaller and smaller.