Physics 1.2 Review Questions

The accepted value of a length measurement is 200 cm, and the experimental value is 198 cm. What is the percentage error of this measurement?

1% error

List two situations in which measurements have an unlimited number of significant figures.

1. a number that is counted 2. exactly defined quantities such as those found within a system of measurement

Round 100.1 degrees celcius to 1 significant figure.

100

What is the result of multiplying 22.34 and 4.9990 with the correct significant figures?

116.7

What is the result of adding 12.2, 3.6, and 44.56 with the correct significant figures?

60.4

Round 65.145 meters to 4 significant figures.

65.15

What is the result of adding 2.75 * 10^4 and 6.75 *10^5?

7.03 * 10

TRUE OR FALSE: An answer is as precise as the most precise measurement from which it was calculated.

False

Compare and contrast accuracy and precision.

Accuracy: the extent to which a given measurement agrees with the standard value for that measurement. Precision: the extent to which a given set of measurements of the same sample agree with their mean

ACCURATE OR PRECISE: A single measurement is within 1% of the correct value.

Accurate

Why are numbers often expressed in scientific notation?

Because it is more convenient to write and calculate with such extreme numbers

ACCURATE OR PRECISE: Four of five repetitions of a measurement were numerically identical, and the fifth varied from the others in value by less than 1%.

Precise

In order to determine if a measurement is precise or not, what would you need to do?

Precision refers to the closeness of two or more measurements to each other, if you weigh something and you get the same weight each time then it is precise

What is the meaning of "accepted value" with respect to an experimental measurement?

The correct value for the measurement.

Circle the letter of each sentence that is true about numbers expressed in scientific notation. a. Scientific notation is written as the product of a coefficient and 10 raised to a power. b. The power of 10 is called the exponent. c. The coefficient is always a number greater or equal to one and less than ten. d. For numbers less than one, the exponent is positive.

a,b,c

Circle the letter of each sentence that is true about significant figures. a. Every nonzero digit in a reported measurement is assumed to be significant. b. Zeros appearing between nonzero digits are never significant. c. Leftmost zeros acting as placeholders in front of nonzero digits in numbers less than one are not significant. d. All rightmost zeros to the right of the decimal point are always significant. e. Zeros to the left of the decimal point that act as placeholders for the first nonzero digit to the left of the decimal point are not significant.

a,c,d,e

How many significant figures do each of the following numbers contain? a. 3400.01 b. 340 c. 0.00340 d. 0.10034 e. 012.0010 * 10^3 f. 340. g. 15 students h. 0034.00 i. 60 min in 1 hour

a. 6 b. 2 c. 3 d. 5 e. 6 f. 3 g. unlimited h. 4 i. unlimited

Is error a measure of accuracy, precision or both? Why?

accuracy only

Circle the letter of the answer in which 503,000,000 is written correctly in scientific notation. a. 5.03 * 10^-7 b. 503 * 10^8 c. 5.03 * 10^8 d. 503 million

c

If a thermometer is calibrated to the nearest degree, to what part of a degree can you estimate a measured temperature?

estimate one beyond the calibration, to the 10th of a degree