Demand is a flow concept because our willingness and ability to buy is subjected to a time period. At different times, we may have different demand schedules. Demand is always related to price and other determinants of demand for a given period of time. Hence, demand is a flow concept.

A flow is a quantity which is measured with reference to a period of time. For instance, income of a person is a flow which is earned during a week or a month or any other period. Likewise, investment (i.e., addition to the stock of capital) is a flow as it pertains to a period of time.

Depreciation is a flow variable. Depreciation reflects the change in value over time and cannot be concretely measured like the assets it is…

Depreciation is a flow since it is measured over a specified period of time. It is time dimensional as it is generally measured over a year.

The circular flow of income or circular flow is a model of the economy in which the major exchanges are represented as flows of money, goods and services, etc. between economic agents. The flows of money and goods exchanged in a closed circuit correspond in value, but run in the opposite direction.

There are three different phases in circular flow of national income, viz. production, income and expenditure. They represent three related aspects, namely, production (i.e., generation of income), distribution (of income) and disposition (of income, i.e., expenditure).

Pure public goods are those that are perfectly non-rivalrous in consumption and non-excludable. Impure public goods are those that satisfy the two conditions to some extent, but not fully. The production of public goods results in positive externalities for which producers don’t receive full payment.

A pure public good is a good which satisfies both non-excludability and non-rivalry assumptions. Examples of pure public goods can be tornado siren,…

Public goods are produced by the government or by nature for the welfare of the people without any cost. But private products are the ones manufactured and sold by private companies to earn a profit.

There are four different types of goods in economics, which can be classified based on excludability and rivalrousness: private goods, public goods, common resources, and club goods. And last but not least, club goods are products that are excludable but non-rival.