Class 8 Exponents And Powers CBSE Questions & Answers

Class 8 · Exponents And Powers

This is Mathematics Class 8 Exponents and Powers CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
\({\left( { - {\text{2}}} \right)^{\text{5}}} \div {\text{ }}{\left( { - {\text{2}}} \right)^{\text{8}}} = {\text{ }}?\)
  • A
    \( - \frac{1}{8}\)
    Correct
  • B
    \( - \frac{1}{5}\)
  • C
    \( - \frac{1}{2}\)
  • D
    \(\frac{1}{8}\)
2
Write the expression using exponents: \({\text{61 }} \times {\text{ 61 }} \times {\text{ 61 }} \times {\text{ 61 }} \times {\text{ 61}}\)
  • A
    \({\text{6}}{{\text{1}}^{\text{5}}}\)
    Correct
  • B
    \({\text{6}}{{\text{1}}^{\text{2}}}\)
  • C
    \({\text{6}}{{\text{1}}^{\text{4}}}\)
  • D
    \({\text{6}}{{\text{1}}^{\text{3}}}\)
3
Evaluate: \({{\text{8}}^{\text{2}}}\)
  • A
    30
  • B
    64
    Correct
  • C
    512
  • D
    8
4
Find the multiplicative inverse of\({{\text{2}}^{--{\text{ 4}}}}\).
  • A
    \({{\text{2}}^{\text{4}}}\)
    Correct
  • B
    \({{\text{2}}^{\text{2}}}\)
  • C
    \({{\text{2}}^{\text{5}}}\)
  • D
    \({{\text{2}}^{\text{3}}}\)
5
Simplify and write in exponential form: \({\left( {--{\text{2}}} \right)^{--{\text{3}}}} \times {\text{ }}{\left( {--{\text{2}}} \right)^{--{\text{ 4}}}}\)
  • A
    \({\left( { - {\text{2}}} \right)^{ - {\text{7}}}}\)
    Correct
  • B
    \({\left( { - {\text{2}}} \right)^{\text{7}}}\)
  • C
    \({\left( {\text{2}} \right)^{\text{7}}}\)
  • D
    \({\left( {\text{2}} \right)^{ - {\text{7}}}}\)
6
The repeated factor in an exponential expression is called ____.
  • A
    exponent
  • B
    base
    Correct
  • C
    None of these
  • D
    power
7
When we have to add numbers in standard form, we convert them into numbers with the ________ exponents.
  • A
    None of these
  • B
    different
  • C
    not equal
  • D
    same
    Correct
8
A group of students were given an assignment to collect different types of leaves. The group collected32 types of leaves. Represent the number of leaves collected in the form of exponential expression with its base being indivisible.
  • A
    \({{\text{2}}^{\text{5}}}\)
    Correct
  • B
    None of these
  • C
    \({{\text{2}}^{\text{4}}}\)
  • D
    \({{\text{2}}^{\text{4}}}\)
9
Evaluate the exponential expression \({\left( { - {\text{b}}} \right)^{\text{4}}} \times {\text{ }}{\left( { - {\text{b}}} \right)^{\text{5}}},{\text{for}}{\text{b}} = {\text{ 4}}.\)
  • A
    None of these
  • B
    262144
  • C
    -282144
  • D
    -262144
    Correct
10
Find the value of the expression \({{\text{a}}^{\text{2}}}\) for a = 10.
  • A
    10
  • B
    None of these
  • C
    1
  • D
    100
    Correct
11
Expand 1025.63 using exponents.
  • A
    \({\text{1 }} \times {\text{ 1}}{0^{\text{4}}} + {\text{ }}0{\text{ }} \times {\text{ 1}}{0^{\text{3}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 5 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 6 }} \times {\text{ 1}}{0^0} + {\text{ 3 }} \times {\text{ 1}}{0^{ - {\text{1}}}}\)
  • B
    None of these
  • C
    \({\text{1 }} \times {\text{ 1}}{0^{\text{3}}} + {\text{ }}0{\text{ }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 5 }} \times {\text{ 1}}{0^0} + {\text{ 6 }} \times {\text{ 1}}{0^{ - {\text{1}}}} + {\text{ 3 }} \times {\text{ 1}}{0^{ - {\text{2}}}}\)
    Correct
  • D
    \({\text{1 }} \times {\text{ 1}}{0^{\text{3}}} + {\text{ }}0{\text{ }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 5 }} \times {\text{ 1}}{0^0} + {\text{ 6 }} \times {\text{ 1}}{0^{ - {\text{1}}}} + {\text{ 3 }} \times {\text{ 1}}{0^{ - {\text{3}}}}\)
12
Expand 1256.249 using exponents.
  • A
    None of these
  • B
    \({\text{1 }} \times {\text{ 1}}{0^{\text{5}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 5 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 6 }} \times {\text{ 1}}{0^0} + {\text{ 2 }} \times {\text{ 1}}{0^{ - {\text{1}}}} + {\text{ 4 }} \times {\text{ 1}}{0^{ - {\text{2}}}} + {\text{ 9 }} \times {\text{ 1}}{0^{ - {\text{3}}}}\)
  • C
    \({\text{1 }} \times {\text{ 1}}{0^{\text{4}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{3}}} + {\text{ 5 }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 6 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 2 }} \times {\text{ 1}}{0^0} + {\text{ 4 }} \times {\text{ 1}}{0^{ - {\text{1}}}} + {\text{ 9 }} \times {\text{ 1}}{0^{ - {\text{2}}}}\)
  • D
    \({\text{1 }} \times {\text{ 1}}{0^{\text{3}}} + {\text{ 2 }} \times {\text{ 1}}{0^{\text{2}}} + {\text{ 5 }} \times {\text{ 1}}{0^{\text{1}}} + {\text{ 6 }} \times {\text{ 1}}{0^0} + {\text{ 2 }} \times {\text{ 1}}{0^{ - {\text{1}}}} + {\text{ 4 }} \times {\text{ 1}}{0^{ - {\text{2}}}} + {\text{ 9 }} \times {\text{ 1}}{0^{ - {\text{3}}}}\)
    Correct
13
Find m so that \({\left( {--{\text{3}}} \right)^m}^{ + {\text{ 1}}} \times {\text{ }}{\left( {--{\text{3}}} \right)^{\text{5}}} = {\text{ }}{\left( {--{\text{3}}} \right)^{\text{7}}}\)
  • A
    1
    Correct
  • B
    3
  • C
    4
  • D
    2
14
Simplify: \({\left( { - {\text{3}}} \right)^{\text{2}}} \times {\left( {\frac{5}{3}} \right)^2}\)
  • A
    27
  • B
    4
  • C
    25
    Correct
  • D
    8
15
Write the expression using exponents: \({\text{89 }} \times {\text{ 89 }} \times {\text{ 89 }} \times {\text{ 89}}\)
  • A
    None of these
  • B
    \({\text{8}}{{\text{9}}^{\text{4}}}\)
    Correct
  • C
    \({\text{8}}{{\text{9}}^{\text{6}}}\)
  • D
    \({\text{8}}{{\text{9}}^{\text{5}}}\)