
The respective number of significant figures for the numbers \[23.023,0.0003\] and \[2.1\times {{10}^{-3}}\] are:
\[A)5,1,2\]
\[B)5,1,5\]
\[C)5,5,2\]
\[D)4,4,2\]
Answer
481.2k+ views
Hint: Significant figures in a particular number refer to the necessary numbers, required to represent that number accurately. To count the number of significant figures in a number, we have a certain set of rules. Going through these rules, we can easily count the number of significant figures in the given numbers.
Complete answer:
Significant figures in a particular number refer to the necessary numbers, required to represent that number accurately. To count the number of significant figures in a number, we have a certain set of rules, as given below:
- All non-zero figures are significant
- All zeroes between two non-zero figures are significant
- Leading zeroes (before non-zero figures) are not significant
- Trailing zeroes (after non zero figures) on right side of decimal are significant
- Trailing zeroes (after non zero figures) on the left side of decimal are significant. However, in case of a non-decimal number, trailing numbers (after non zero figures) are not significant
Now, let us count the number of significant figures in the given numbers using these rules.
\[a)23.023\]
According to the rule, ‘All zeroes between two non-zero figures are significant’, all the given figures in the number are significant and hence, the total number of significant numbers is $5$.
\[b)0.0003\]
According to the rule, ‘Leading zeroes (before non-zero figures) are not significant’, all the numbers except $3$ are not significant and hence, the number of significant figures is $1.$
\[c)2.1\times {{10}^{-3}}\]
The number can be written as $0.0021$. According to the rule, ‘Leading zeroes (before non-zero figures) are not significant’, all the numbers except $2$ and $1$ are not significant and hence, the number of significant figures is $2$.
Therefore, from the above explanation, it is clear that the correct answer is option $A$.
Note:
All the given rules for significant and non-significant figures need to be remembered to solve such questions. The fifth/last rule stated in the above set of rules needs to be clearly differentiated since this rule is tricky and can always be a reason for confusion.
Complete answer:
Significant figures in a particular number refer to the necessary numbers, required to represent that number accurately. To count the number of significant figures in a number, we have a certain set of rules, as given below:
- All non-zero figures are significant
- All zeroes between two non-zero figures are significant
- Leading zeroes (before non-zero figures) are not significant
- Trailing zeroes (after non zero figures) on right side of decimal are significant
- Trailing zeroes (after non zero figures) on the left side of decimal are significant. However, in case of a non-decimal number, trailing numbers (after non zero figures) are not significant
Now, let us count the number of significant figures in the given numbers using these rules.
\[a)23.023\]
According to the rule, ‘All zeroes between two non-zero figures are significant’, all the given figures in the number are significant and hence, the total number of significant numbers is $5$.
\[b)0.0003\]
According to the rule, ‘Leading zeroes (before non-zero figures) are not significant’, all the numbers except $3$ are not significant and hence, the number of significant figures is $1.$
\[c)2.1\times {{10}^{-3}}\]
The number can be written as $0.0021$. According to the rule, ‘Leading zeroes (before non-zero figures) are not significant’, all the numbers except $2$ and $1$ are not significant and hence, the number of significant figures is $2$.
Therefore, from the above explanation, it is clear that the correct answer is option $A$.
Note:
All the given rules for significant and non-significant figures need to be remembered to solve such questions. The fifth/last rule stated in the above set of rules needs to be clearly differentiated since this rule is tricky and can always be a reason for confusion.
Recently Updated Pages
Express the following as a fraction and simplify a class 7 maths CBSE

The length and width of a rectangle are in ratio of class 7 maths CBSE

The ratio of the income to the expenditure of a family class 7 maths CBSE

How do you write 025 million in scientific notatio class 7 maths CBSE

How do you convert 295 meters per second to kilometers class 7 maths CBSE

Write the following in Roman numerals 25819 class 7 maths CBSE

Trending doubts
State and prove Bernoullis theorem class 11 physics CBSE

What are Quantum numbers Explain the quantum number class 11 chemistry CBSE

Write the differences between monocot plants and dicot class 11 biology CBSE

1 ton equals to A 100 kg B 1000 kg C 10 kg D 10000 class 11 physics CBSE

State the laws of reflection of light

In northern hemisphere 21st March is called as A Vernal class 11 social science CBSE
