NCERT Solutions for Class 8th Maths Chapter 2 Power Play

About this chapter

n a means n multiplied by itself a times. Here n is the base and a is the exponent (or power). 5 4 = 5 × 5 × 5 × 5 = 625. The five working rules: n a × n b = n a+b , (n a ) b = n ab , n a ÷ n b = n a–b , m a × n a = (mn) a and m a ÷ n a = (m ÷ n) a . n 0 = 1 and n –a = 1/n a (for n ≠ 0) are not extra rules — they are the only definitions that let n a ÷ n b = n a–b keep working when a = b or a Exponential growth multiplies by a fixed factor at each step; linear growth adds a fixed amount. 46 folds reach the Moon, while 192.2 crore ladder steps are needed to do the same job. Scientific notation writes a number as x × 10 y with 1 ≤ x Powers of 10 give names to huge quantities: lakh 10 5 , crore 10 7 , arab 10 9 , kharab 10 11 , neel 10 13 , padma 10 15 ; million 10 6 , billion 10 9 , trillion

• .1 Experiencing the Power Play …
• .2 Exponential Notation and Operations
• .2 Exponential Notation and Operations · Magical Pond
• .3 The Other Side of Powers
• .3 The Other Side of Powers · Power Lines
• .4 Powers of 10
• .4 Powers of 10 · Scientific Notation
• .5 Did You Ever Wonder?
• .5 Did You Ever Wonder? · Getting a Sense for Large Numbers
• .5 Did You Ever Wonder? · A different way to say your age!