Unit And Dimensions - NEET Physics Questions
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Unit And Dimensions

Question 111: easy

In an experiment, the percentage error occurring in the measurements of physical quantities \( A \), \( B \) and \( C \) are 1%, 2% and 3% respectively. If a physical quantity \( X \) is such that \( X = \frac{AB^2}{C^3} \), then the percentage error in the calculation of \( X \) can be

1. 1%
2. 2%
3. 3%
4. 4%
View Answer

By taking systematic errors into account, the relative error can be written with signs: \( \frac{\Delta X}{X} = \pm \frac{\Delta A}{A} \pm 2\frac{\Delta B}{B} \pm 3\frac{\Delta C}{C} \). The minimum absolute error is \( |1 + 4 - 9|\% = 4\% \), so 4% is a possible value.

Question 112: easy

Sum of the numbers \(436.32\text{ g}\), \(227.2\text{ g}\) and \(0.301\text{ g}\) is

1. 663.821 g
2. 663.8 g
3. 6663.82 g
4. 664 g
View Answer

In addition, the final result must be rounded off to the least number of decimal places of the terms. Here, \(227.2\text{ g}\) has one decimal place, so the sum \(663.821\text{ g}\) is rounded to \(663.8\text{ g}\).