State the number of significant figures in the following:

A. 0.007 m2


B. 2.64 × 1024 kg


C. 0.2370 g cm–3


D. 6.320 J


E. 6.032 N m–2


F. 0.0006032 m2

A. 1


Explanation: Significant figure- 7. If number is less than one, then 0’s before 7 are insignificant (note that there are only 0’s before 7 and numbers like 0.1007 will have 0 as significant figure)


B. 3


Explanation: Significant figure- 2, 6, 4. Powers of 10 are not taken in counting for significant figures.


C. 4


Explanation: Significant figure- 2,3, 7, 0. Trailing 0’s are significant. These 0’s increase the accuracy of the answer.


D. 4


Explanation: Significant figure- 6, 3, 2, 0. (similar to the problem C)


E. 4


Explanation: Significant figure- 6, 0, 3, 2. 0’s between 2 non-zero digits are significant.


F. 4


Explanation: Significant figure- 6, 0, 3, 2. (similar to the problem A and E)


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