Tag: units and measurement: error analysis

Questions Related to units and measurement: error analysis

The value due regard to significant figure  $ 4.0\times 10^{-4}-2.5\times 10^{-6}$ 

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $\displaystyle 4.0\times 10^{-4}$

  2. $\displaystyle 3.975\times 10^{-4}$

  3. $\displaystyle 3.9\times 10^{-4}$

  4. none of the above

Show answer
Correct Option: B
Explanation:
The value of this case is,
$4.0\times 10^{-4}-2.5\times 10^{-6}$
$=3.975\times 10^{-4}$.

Length, breadth and thickness of a rectangular slab are 4.234 m, 1.005 m and 2.01 m respectively. Find volume of the slab to correct significant figures.

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $\displaystyle 8.55 m^{3}$

  2. $\displaystyle 8.552 m^{3}$

  3. $\displaystyle 8.6 m^{3}$

  4. None of the above

Show answer
Correct Option: A
Explanation:

l = 4.234 m 4 significant figures

b = 1.005 m 4 significant figures
w = 2.01 m 3 significant figures 
Therefore, Volume = lbw= 8.55 .........3 significant figures

Write down the number of significant figures in the following value.

$0.0628 cm$

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $four$

  2. $three$

  3. $two$

  4. $one$

Show answer
Correct Option: B
Explanation:

Zeroes before, a non zero digit are not significant.

Therefore, (B) three significant figures in 0.0628

Round off following number upto four significant figures.

$2.00823$

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $2.008$

  2. $2.0082$

  3. $2.0083$

  4. $2$

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Correct Option: A
Explanation:

$2.00823 = 2.008$ because the digit 2 is less than 5.

Write down the number of significant figures in 12.00 N.

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. four

  2. three

  3. two

  4. one

Show answer
Correct Option: A
Explanation:

According to general rule for determining of number of significant figures, zeroes placed after other digits but behind a decimal point are significant. Thus 12.00 has four significant figures. 

Write down the number of significant figures in 0.00628 cm.

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. four

  2. three

  3. two

  4. one

Show answer
Correct Option: B
Explanation:

Zeroes before any non zero value are not significant.

Therefore, 0.00628 has three significant figures.

Write down the number of significant figures in the following.

$62.00m$

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $four$

  2. $three$

  3. $two$

  4. $one$

Show answer
Correct Option: A
Explanation:

Zeroes after decimal but after non zero value are significant.

Therefore, 62.00 has four significant figure.

Write down the number of significant figures in the following.
$6428$

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $four$

  2. $three$

  3. $two$

  4. $one$

Show answer
Correct Option: A
Explanation:

For a number with $NO \ \ ZERO$ to the right, the number of significant figures is simply the total number of digits.

Here the total significant figures is $4$.

The area of rectangle of size 1.23cm $ \times $ 2.345cm is ?

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. $ 2.88cm^2 $

  2. $ 2.884cm^2 $

  3. $ 2.9cm^2 $

  4. $ 2.88435cm^2 $

Show answer
Correct Option: A
Explanation:

$1.23\times 2.345=2.88$

Since final answer should be expressed in 3 significant figures because least number of significant figures in question are 3.

The significant digits in 200.40 are ?

physics units and measurement: error analysis significant figures significant figures and rounding of digits units and measurements

  1. 4

  2. 5

  3. 2

  4. 3

Show answer
Correct Option: B
Explanation:

All the digits in 200.40 are significant since zeroes after non zero digit after decimal are significant . 

Therefore, (B) 5 is correct answer.