Question

Cities are going faster than the capacity of the economy to support them? Explain its effects

Answer 1

That doesn’t make sense. The economy does not support cities. Cities are institutions people use to (among other things) support the economy.

Generally, people in cities are both more productive and cheaper to support than people living outside cities. So if the economy is having trouble supplying necessities to the population, growth of cities would help, not hurt.

So I think you are alleging that people are moving to cities and becoming less productive and/or more expensive to support. If that were true, people would leave cities.

So to have bad economic effects from excessive urban growth, we have to assume people are moving to cities, failing to find work, and being prevented from leaving. If that were true, the effects would obviously be urban poverty and decay.

However, urban poverty and decay are could result from many other causes. If your solution to urban problems is to force people out of cities, you would almost certainly find that you made the situation worse.