number of unit cells

A square matrix A=[a i j ] n x n is called an identity or unit matrix if (2) a i j =1 for all i = j In other words a square matrix each of whose diagonal elements is unity and each of whose non-diagonal elements is equal to zero is called an identity or unit matrix. The..

If a and b are two quantities with the same units such that b is not equal to zero; then the quotient a/b is called the ratio between a and b. It is written as a:b. Ratio does not have any unit. The quantities a and b are called terms of the ratio. a' is called antecedent ..

The number of significant figures depends on the instrument used and accuracy required. It is wrong to record diameter as 2 cm. It means the reading is approximated to the nearest 1 cm. If the exact reading is 2 cm then it should be recorded as 2.0 cm. The significant fi..

Definition of ratio - If a and b are two quantities with the same units such that ; then Ratio does not have any unit. The quantities a and b are called terms of the ratio. a' is called antecedent (first term) b' is called consequent (second te..

De Moivre's formula, named after Abraham de Moivre, states that for any complex number (and, in particular, for any real number) x and any integer n it holds that The formula is important because it connects complex numbers (i stands for the imaginary unit..

Let us consider the following entries in a Students' Journal: (a) Weight of a calorimeter = 42 g (measuring instrument used is spring balance) The smallest reading the spring balance can record is 1g. There are 42 of 1 g units of measurement. Hence, there are two significant figures in th..

We use specific number of digits to denote an exact value of a number for required accuracy. The digits used for such a purpose are called significant figures. Suppose a measurement is recorded as 0.6204 cm. It means that the measurement was made correct to the nearest 0.0001 cm..

2.793 represents 2 units, seven-tenths, nine-hundredths and three-thousandths or using fraction notation: (a) (b)..

Summary - A matrix is a rectangular array of numbers, arranged in rows and columns. Order of a matrix = Number of rows in it x Number of columns in it Row matrix is a matrix with only one row. Column matrix is a matrix with only one column. Zero or Null matrix is a mat..

We know that the digits of a number, one by one in order from left to right decrease in value rapidly. Let us illustrate it by examples. Mass of a gold ornament is 23.473 g. Round off to (i) two decimal places, (ii) one decimal place. 23.473 g = (2 x 10) + (3 x 1) + The successive digits ..