Introduction to Significant Figures Video Lecture | Physics Class 11 - NEET

Ans. Significant figures are the digits in a number that carry meaningful information about the precision of a measurement. They help express the accuracy and reliability of a measurement by indicating the number of digits that are known with certainty. Significant figures are important in scientific measurements because they ensure that the reported value reflects the precision of the measuring instrument and the accuracy of the measurement process.

Ans. To determine the number of significant figures in a measurement, follow these rules: - All non-zero digits are significant. For example, in the number 345, all three digits are significant. - Zeros between non-zero digits are significant. For example, in the number 506, the zero is significant. - Leading zeros (zeros to the left of the first non-zero digit) are not significant. For example, in the number 0.045, the zero is not significant. - Trailing zeros (zeros to the right of the last non-zero digit) are significant if they appear after a decimal point. For example, in the number 2.00, both zeros are significant. - Trailing zeros that serve as placeholders are not significant. For example, in the number 200, the zeros are not significant unless specified otherwise.

Ans. When performing calculations involving significant figures, the result should be reported with the same number of significant figures as the least precise measurement used in the calculation. Here are some guidelines: - Addition and subtraction: The result should be rounded to the same number of decimal places as the measurement with the fewest decimal places. - Multiplication and division: The result should be rounded to the same number of significant figures as the measurement with the fewest significant figures. - For intermediate steps, it's best to carry out the full calculation without rounding and only round the final result.

Ans. No, it is not appropriate to have more significant figures in the result of a calculation than in the original measurements. The result should not be reported with more significant figures than the least precise measurement used in the calculation. It is important to maintain consistency and avoid implying a higher level of precision than actually exists in the measurements.

Ans. Yes, there are a few exceptions to the rules of determining significant figures: - Exact numbers, such as counting objects or defined constants, have an infinite number of significant figures. For example, if you have 5 apples, the number 5 is considered to have an infinite number of significant figures. - In logarithmic functions, the number of significant figures is determined by the number of digits after the decimal point. For example, in log(0.050), the significant figures are determined by the decimal places, not the leading zeros.