Determinants of Demand:
(1) Changes in Tastes and Fashions: The demand for some goods and services is very susceptible to changes in tastes and fashions
(2) Changes in Weather: An unusually dry summer results in a increase in the demand for cool drinks.
(3) Taxation and Subsidy: If fresh taxes are levied or the existing rates of taxation on commodities are increased their prices go up. The subsidies will bring down the prices. Therefore taxes reduce demand and subsidies raise demand.
(4) Changes in Expectations: Expectations also bring about a change in demand. Expectation of rise in price in future results in increase in demand.
(5) Changes in Savings: Savings and demand are inversely related.
(6) State of Trade Activity: During the periods of boom and prosperity, the demand for all commodities tends to increase. On the contrary, during times of depression there is a general slackening of demand.
(7) Advertisement: In advanced capitalistic countries advertising is a powerful instrument increasing the demand in the market.
(8) Changes in Income: An increase in family income may increase the demand for durables like video recorders and refrigerators. Equal distribution of income enables poor to get more income. As a result consumption level increases.
(9) Change in Population: The demand for goods depends on the size of population. An increase in population tends to increase the demand for goods and a decrease in population tends to decrease the demand (if other things remain constant).

(i) Indifference curve must have a negative slope.
(ii) Indifference curves are convex to the origin.
(iii) Indifference curve cannot intersect
(iv) Indifference curve do not touch the horizontal or vertical axis

(i) A consumer wants to spend his limited income on apple and orange.
(ii) He will be in equilibrium when he gets maximum satisfaction.

\(\mathrm{K}=\frac{M \mathrm{U_A}}{\mathrm{P_A}}=\frac{M U_O}{\mathrm{P_O}}\)
If \(\frac{MU_A}{P_ A}\) is less than \(\frac{M U_O}{P_O}\) he would transfer money from apple to orange till both are equal.

Total utility	Marginal utility
Increases at a diminishing rate	Goes on diminishing
Reaches maximum	Becomes zero
Diminishes	Becomes negative

Characteristics
Wants are unlimited
(i) Wants are countless and various in kinds.
(ii) When one want is satisfied another want arises.
Wants become habits
(i) When a man starts reading newspaper in the morning it becomes a habit.
Wants are satiable
(i) We can satisfy particular wants at a given time.
(ii) When one feels hungry, he takes food and that want is satisfied.
Wants are alternative
(i) There are alternative ways to satisfy a particular want (eg) idly, dosa.
Wants are competitive
(i) There is competition among wants.
(ii) So we have to choose more urgent wants and satisfy them first.
Wants are complementary
(i) Satisfaction of a particular want requires the use of more than one commodity. (eg) car and petrol.
Wants are recurring
(i) Some wants occur again and again. For ex. if we feel hungry, we take food and satisfy our want.
(ii) But after some time we again feel hungry and want food.