NCERT Solutions for Class 8 Maths Chapter 10: Students can aim for excellent exam scores by using the NCERT Solutions for Class 8 Chapter 10 Exponents and Powers. To comprehend the topics taught in this chapter, consult the NCERT Class 8 Mathematics Exercise Solutions and rehearse the questions and answers based on the CBSE syllabus.
We can refer to an expression as a power if it shows the same factor being multiplied repeatedly. In the case of 42, for instance, the base is the number 4, and the exponent is the number 2. The number of times the base is used as a factor in an expression is represented by an exponent.NCERT Solutions for Class 8 Maths Chapter 10 PDF
1. Evaluate:
(i) 3 -2 (ii) (-4) -2 (iii) (1/2) -5
Solution:
(i) 3 -2 = (1/3) 22. Simplify and express the result in power notation with a positive exponent:
(i) (-4) 4 ÷(-4) 8
(ii) (1/2 3 ) 2
(iii) -(3) 4 ×(5/3) 4
(iv) (3 -7 ÷3 -10 )×3 -5
(v) 2 -3 ×(-7) -3
Solution:
(i)
(iv)
(v) 2 -3 ×(-7) – 3
= (2×-7) -3 (Because a m ×b m = (ab) m ) = 1/(2×-7) 33. Find the value of:
(i) (3 0 +4 -1 )×2 2
(ii) (2 -1 ×4 -1 )÷2 – 2
(iii) (1/2) -2 +(1/3) -2 +(1/4) -2
(iv) (3 -1 +4 -1 +5 -1 ) 0
(v) {(-2/3) -2 } 2
Solution:
(i)(3 0 +4 – 1 )×2 2 = (1+(1/4))×2 2
(ii)(2 -1 ×4 -1 )÷2 -2
= [(1/2)×(1/4)] ÷(1/4)(iv) (3 -1 +4 -1 +5 -1 ) 0
= 14. Evaluate:
(i) (8 -1 ×5 3 )/2 -4
(ii) (5 -1 ×2 -2 )×6 -1
Solution:
(i) (8 -1 ×5 3 )/2 -4
(ii) (5 -1 ×2 -2 )×6 -1
5. Find the value of m for which 5 m ÷ 5 -3 = 5 5
Solution:
5 m ÷ 5 -3 = 5 5 5 (m-(-3) ) = 5 56. Evaluate:
(i)
(ii)
Solution:
(i)
(ii)
7. Simplify the following:
(i)
(ii)
(i)
(ii)
1. Express the following numbers in standard form.
(i) 0.0000000000085
(ii) 0.00000000000942
(iii) 6020000000000000
(iv) 0.00000000837
(v) 31860000000
Solution:
(i) 0.0000000000085 = 0.0000000000085×(10 12 /10 12 ) = 8.5 ×10 -12 (ii) 0.00000000000942 = 0.00000000000942×(10 12 /10 12 ) = 9.42×10 -12 (iii) 6020000000000000 = 6020000000000000×(10 15 /10 15 ) = 6.02×10 15 (iv) 0.00000000837 = 0.00000000837×(10 9 /10 9 ) = 8.37×10 -9 (v) 31860000000 = 31860000000×(10 10 /10 10 ) = 3.186×10 102. Express the following numbers in the usual form.
(i) 3.02×10 -6
(ii) 4.5×10 4
(iii) 3×10 -8
(iv) 1.0001×10 9
(v) 5.8×10 12
(vi) 3.61492×10 6
Solution:
(i) 3.02 × 10 -6 = 3.02/10 6 = 0 .00000302 (ii) 4.5 × 10 4 = 4.5 × 10000 = 45000 (iii) 3 × 10 -8 = 3/10 8 = 0.00000003 (iv) 1.0001 × 10 9 = 1000100000 (v) 5.8 × 10 12 = 5.8 × 1000000000000 = 5800000000000 (vi) 3.61492 × 10 6 = 3.61492 × 1000000 = 36149203. Express the number appearing in the following statements in standard form.
(i) 1 micron is equal to 1/1000000 m. (ii) The charge of an electron is 0.000, 000, 000, 000, 000, 000, 16 coulomb. (iii) Size of bacteria is 0.0000005 m (iv) The size of a plant cell is 0.00001275 m (v) The Thickness of a thick paper is 0.07 mm
Solution:
(i) 1 micron = 1/1000000
= 1/10 6 = 1×10 -6(ii) The charge of an electron is 0.00000000000000000016 coulombs
= 0.00000000000000000016 × 10 19 /10 19 = 1.6 × 10 -19 coulomb(iii) Size of bacteria = 0.0000005
= 5/10000000 = 5/10 7 = 5×10 -7 m(iv) The size of a plant cell is 0.00001275 m
= 0.00001275×10 5 /10 5 = 1.275×10 -5 m(v) Thickness of a thick paper = 0.07 mm
0.07 mm = 7/100 mm = 7/10 2 = 7×10 -2 mm4. In a stack, there are 5 books, each having a thickness of 20 mm, and 5 paper sheets, each having a thickness of 0.016 mm. What is the total thickness of the stack?
Solution: The thickness of one book = 20 mm Thickness of 5 books = 20×5 = 100 mm The thickness of one paper = 0.016 mm Thickness of 5 papers = 0.016×5 = 0.08 mm Total thickness of a stack = 100+0.08 = 100.08 mm = 100.08×10 2 /10 2 mmStructured Learning : NCERT solutions provide a structured approach to solving problems, following the curriculum guidelines set by educational boards. This helps students to stay organized and focused on the topics covered in the chapter.
Concept Clarity : The solutions help clarify concepts related to exponents and powers by providing step-by-step explanations. This is crucial for students to grasp the underlying principles and applications of exponents in mathematical problems.
Variety of Problems : NCERT solutions typically cover a variety of problems ranging from basic to advanced levels. This variety helps students to practice different types of questions and enhances their problem-solving skills.
Accuracy and Reliability : NCERT solutions are prepared by experts in the field, ensuring accuracy in the solutions provided. This reliability is important for students and teachers alike, as they can trust the correctness of the information and solutions provided.
Exam Preparation : By practicing with NCERT solutions, students can familiarize themselves with the type of questions that are likely to appear in exams. This helps them to prepare effectively and perform well in their assessments.
Self-assessment and Improvement : NCERT solutions enable students to self-assess their understanding of the chapter. They can identify areas where they may need more practice or further clarification, allowing for targeted improvement.
Encourages Independence : Using NCERT solutions encourages students to think independently and develop their problem-solving skills. They learn how to approach different types of problems and develop confidence in their mathematical abilities.
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