Electrical quantities such as resistance, voltage, power, inductance and capacitance can have very large values. For example a power station can generate 1,000,000,000 watts of power, similarly an inductor can have a value of 0.00001 H. To keep things straight forward, a common practice is to use prefixes. Each prefix represents a power of ten. The table below display top 7 prefixes that are very common in Electrical and Electronics Engineering.

NumberPower of 10PrefixSymbol
1 000 000 000 109 gigaG
1 000 000106megaM
1 000103 kilok
0.00110-3 millim
0.000 00110-6 microμ
0.000 000 00110-9 nanon
0.000 000 000 00110-12 picop

Examples

Example 1: Express 33000 V in kilovolts.

Solution: Multiply and divide the number by 1000

= 33000 V * (1000/1000)

= (33000/1000) V * 1000

= 33 kV


Example 2: Express 0.222 A in milliAmps.

Solution: Multiply and divide the number by 0.001.

= 0.222 * (0.001/0.001) A

= 0.222 * (m/0.001) A

= (0.222/0.001) mA

= 222 mA