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A tariff increases the price of imported goods, reducing consumer surplus. Previously, consumer surplus was the area between the demand curve and the world price line. With the tariff, the domestic price rises, shrinking consumer surplus as consumers either pay higher prices or reduce consumption. This loss reflects both the price increase and the decreased quantity purchased.

Tariffs reduce competition from cheaper international suppliers, allowing domestic producers to sell at higher prices. Producer surplus increases, represented by the area between the supply curve and the new higher price line. Domestic producers can expand production and capture greater market share due to less competitive pressure from foreign goods.

Government revenue from a tariff equals the tariff rate multiplied by the quantity of imported goods after the tariff is imposed. For example, if a country imposes a tariff on imported coffee beans, the revenue is calculated by multiplying the tariff rate by the quantity of coffee beans imported at the new higher price level.

Deadweight loss arises from two sources: inefficient production, where domestic producers replace more efficient foreign producers, and reduced consumption, as consumers forgo purchases due to higher prices. This loss represents a reduction in overall economic welfare and market efficiency, indicating the net cost to society from the tariff.

Tariffs protect domestic industries by making imported goods more expensive and less competitive. This reduces international trade by decreasing the quantity of imports. While tariffs shield local producers from foreign competition, they also limit consumer access to cheaper foreign goods and reduce overall trade between countries.

A tariff raises the equilibrium price above the world price level. The new domestic price includes the tariff cost, making imported goods more expensive. This higher equilibrium price reduces the total quantity of goods consumed in the domestic market, as the market adjusts to the increased cost of imports.

Tariffs protect domestic producers and generate government revenue, but they increase consumer prices, reduce trade, and create deadweight loss. Consumers lose surplus while producers gain, and overall economic welfare decreases due to inefficiencies. The benefits to domestic industries come at the expense of consumers and foreign suppliers.