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Question
Answer the following question.
Describe what is meant by order of magnitude.
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Solution
Order of magnitude:
The magnitude of any physical quantity can be expressed as A × 10n where ‘A’ is a number such that 0.5 ≤ A < 5 then, ‘n’ is an integer called the order of magnitude.
Examples:
- Speed of light in air = 3 × 108 m/s ∴ order of magnitude = 8
- Mass of an electron = 9.1 × 10-31 kg = 0.91 × 10–30 kg
∴ order of magnitude = – 30.
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