Test: Uncertainty in Measurement (NCERT) - NEET MCQ

8008 = 8.008 x 10³

• Step 1: Move the decimal point so that you have a number that is between 1 and 10. ...
• Step 2: Count the number of decimal places moved in Step 1 . ...
• Step 3: Write as a product of the number (found in Step 1) and 10 raised to the power of the count (found in Step 2).

Zero between two non - zero digits are significant.

1. The result of an addition or subtraction is reported to the same number of decimal places as present in number with the least decimal places.

2. The result of multiplication or division should be rounded off to the same number of significant figures as present in number with the least significant number.

3. The result of multiplication or division should be rounded off to the same number of significant figures as present in the least precise figure.

4. The non-significant figures in the measurements are rounded off.

option B is correct

2.5 x 1.25 = 3.125
Since 2.5 has two significant figures, the result should not have more than two significant figures. Hence, the answer will be 3.1.

0.010100 x 10³ contains 5 significant figures.

3.0223 + 5.041 = 8.0633
Since, 5.041 has only 3 digits after the decimal point, the result should be reported to 3 digits after decimal point.

9.000 m is the most accurate measurement as it is most precise among the given options.

Rule: The result of an addition or subtraction is reported to the same number of decimal places as present in number with the least decimal places.

Since the least precise number is 2.300 and that has three digits after the decimal, therefore the result of the above addition is rounded off to three decimal figures as 2.340.

126,000 has 3 significant figures as zeros are not counted

15.15μs = 15.15×10−6 s = 1.515×10−5 s

0.0048 = 4.8×10−3

Hence, the correct option is D.

Since 1 L = 1000 cm³ and 1 m = 100 cm

Seconds in 3 days can be calculated as