Measuring Techniques and Quantities

What is the SI unit for length?

• centimeter

• millimeter

• kilometer

• meter

Define accuracy in measurements.

• Accuracy is the total number of measurements taken.

• Accuracy is the same as precision in measurements.

• Accuracy refers to the consistency of repeated measurements.

• Accuracy is the degree to which a measurement reflects the true value.

What is the difference between accuracy and precision?

• Accuracy is about correctness; precision is about consistency.

• Accuracy is the degree of detail; precision is the level of effort.

• Accuracy is about the number of attempts; precision is about the time taken.

• Accuracy measures the average; precision measures the total.

How many significant figures are in the number 0.00456?

• 5

• 4

• 2

• 3

What is the unit of mass in the SI system?

• gram

• kilogram

• ounce

• pound

Explain the term 'significant figures'.

• Significant figures are the total number of digits in a number.

• Significant figures refer to the number of decimal places only.

• Significant figures are irrelevant in scientific calculations.

• Significant figures are the digits in a number that indicate its precision.

What type of error occurs due to limitations of measuring instruments?

• Measurement error

• Random error

• Systematic error

• Instrumental error

How do you round the number 0.00789 to two significant figures?

• 0.008

• 0.0078

• 0.0079

• 0.007

What is the formula for calculating percentage error?

• (True Value - Measured Value) * 100%

• (Measured Value + True Value) / 2

• (Measured Value / True Value) * 100%

• (|Measured Value - True Value| / True Value) * 100%

What is the difference between systematic and random errors?

• Systematic errors occur only in scientific experiments.

• Random errors can be controlled and eliminated completely.

• Systematic errors are consistent and repeatable, while random errors are unpredictable and vary.

• Systematic errors are always larger than random errors.