How would a contractionary monetary policy affect the exchange rate, net exports, aggregate demand, and aggregate supply?

A contractionary monetary policy refers to the central bank's actions aimed at decreasing the money supply in the economy. This is usually done by increasing interest rates or through open market operations (selling government securities). The main goal of such a policy is to fight inflation and reduce economic growth, as higher interest rates discourage borrowing and spending.

Contractionary monetary policy leads to an increase in domestic interest rates. As interest rates rise, foreign investors become more attracted to the domestic currency, increasing demand for it. The increased demand leads to an appreciation of the domestic currency's value, making the exchange rate stronger. In other words, the domestic currency becomes more valuable relative to foreign currencies.

The appreciation of the domestic currency makes domestic goods more expensive for foreign consumers, reducing the demand for exported goods. At the same time, imports become cheaper due to the stronger currency, leading to an increase in imports. Thus, net exports (exports minus imports) decrease as a result of contractionary monetary policy.

Aggregate demand is the sum of consumption, investment, government spending, and net exports. Contractionary monetary policy increases interest rates, discouraging businesses from borrowing and investing, and individuals from spending. This reduces consumption and investment, leading to a lower aggregate demand. Additionally, as mentioned in Step 3, net exports also decrease. Thus, all components of aggregate demand are negatively affected, leading to an overall decrease in aggregate demand.

Aggregate supply is not directly affected by contractionary monetary policy. However, when aggregate demand decreases, businesses tend to reduce production and lower their prices, which can lead to a short-term decrease in aggregate supply. Furthermore, as interest rates rise, companies may find borrowing for capital investments more expensive and therefore cut back on investments, which could impact long-term aggregate supply. However, these indirect effects depend on businesses' responses and the overall state of the economy. In conclusion, contractionary monetary policy can lead to a stronger exchange rate, decreased net exports, reduced aggregate demand, and potential indirect effects on aggregate supply. These outcomes help to control inflation and slow down economic growth, which are the primary objectives of such a policy.