Physics Sec 2
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SI
(Blank) is the standard measurement system for science.
Smallest
*/divide: The final answer has the same number of significant figures as the measurement having the (blank) number of significant figures.
+/-
Given that (blank) take place in columns, round the final answer to the first column from the left containing an estimated digit
standard deviation
If enough trials are performed for an experiment, graphing the data points and calculating the (blank) can provide an indication of the quality of the data set, as well as helping to identify any errors.
Method
If some measurements are taken using one method and some are takenusing a different method, a type of error called (blank) error will result. It can be greatly reduced by standardizing the method of taking measurements.
Newtons
In other cases, it may appear that a new unit that is not one of the base units is being introduced, but often these new units merely serve as shorthand ways to refer to combinations of units. For example, forces and weights are typically measured in units of (blank), but it is defined as being exactly equivalent to one kilogram multiplied by meters per second squared (1 kg•m/s2).
3 Estimated
In the case of the measurement of the pencil as about 18.2 cm, the measurement has (blank) significant figures. The significant figures of a measurement include all the digits that are actually measured (18 cm), plus one (blank) digit. Note that the number of significant figures is determined by the precision of the markings on the measuring scale. The last digit is reported as a 0.2 (for the estimated 0.2 cm past the 18 cm mark). Because this digit is an estimate, the true value for the measurement is actually somewhere between 18.15 cm and 18.25 cm.
Sig figs
It is important to record the precision of your measurements so that other people can understand and interpret your results. A common convention used in science to indicate precision is known as (blank).
Derived Units
Not every observation can be described using one of these units, but the units can be combined to form (blank).
Scientific notation
One way to solve such problems is to report all values using (blank). In scientific notation, the measurement is recorded to a power of 10, and all of the figures given are significant. For example, if the length of 230 cm has two significant figures, it would be recorded in scientific notation as 2.3 × 10^2 cm. If it has three significant figures, it would be 2.30 * 10^2cm
Accuracy Precision Instrument
Poor (blank) involves errors that can often be corrected. On the otherhand, (blank) describes how exact a measurement can possibly be. For example, a measurement of 1.325 m is more precise than a measurementof 1.3 m. A lack of precision is typically due to limitations of the measuring (blank) and is not the result of human error or lack of calibration. Forexample, if a meterstick is divided only into centimeters, it will be difficult to measure something only a few millimeters thick with it.
Prefixes 10
SI uses (blank) to accommodate extremes. Physics is a science that describes a broad range of topics and requires a wide range of measurements, from very large to very small. For example, distance measurements can range from the distances between stars (about 100 000 000 000 000 000 m) to the distances between atoms in a solid (0.000 000 001 m). Because these numbers can be extremely difficult to read and write, they are often expressed in powers of (blank)
Zero
When the last digit in a recorded measurement is a (blank), it is difficult to tell whether it is there as a placeholder or as a significant digit. For example, if a length is recorded as 230 mm, it is impossible to tell whether this number has two or three significant digits. In other words, it can be difficult to know whether the measurement of 230 mm means the measurement is known to be between 225 mm and 235 mm or is known more precisely to be between 229.5 mm and 230.5 mm.
Even
When the rounding digit is a 5 go to the nearest (Blank) number
Temperature Electrical current
When we learn about heat and electricity, we will need to add two other dimensions to our list, one for (blank) and one for (blank).
Length mass time
You are probably already familiar with three basic dimensions: (blank), (blank), & (blank)
Left
Zeros at the end of a number but to the (blank) of a decimal are significant if they have been measured or are the first estimated digit; otherwise, they are notsignificant.
Sig
Zeros between other nonzero digits are (blank)
Not sig
Zeros in front of nonzero digits are (blank)
Sig
Zeros that are at the end of a number and also to the right of the decimal are (blank).
Even Round down
if the last significant figure is an (blank) number and the next digit is a 5, with no other nonzero digits-
Round down
whenever the digit following the last significant figure is a 0, 1, 2, 3, or 4
% error
For some types of data, the accuracy of an individual value or of an average experimental value can be compared quantitatively with the correct, or accepted, value by calculating the (blank)
Instrument
Another type of error is (blank) error. If a meterstick or balance is not in good working order, this will introduce error into any measure-ments made with the device. For this reason, it is important to be careful with lab equipment. Rough handling can damage balances. If a wooden meterstick gets wet, it can warp, making accurate measurements difficult.
Instrument
Experimental work is never free of error, but it is important to minimize error in order to obtain accurate results. An error can occur, for example, if a mistake is made in reading an (blank) or recording the results. One way to minimize error from human oversight or carelessness is to take repeated measurements to be certain they are consistent.
Confidence
A lower uncertainty indicates greater (blank). Uncertainties are usually expressed by using statistical methods.
Uncertainty
A numeric measure of confidence in a measurement or result is known as (blank).
Accuracy Precision
Because theories are based on observation and experiment, careful measurements are very important in physics. But no measurement is perfect. In describing the imperfection of a measurement, one must consider both the (blank), which describes how close the measurement is to the correct value, and the (blank), which describes how exact the measurement is. Although these terms are often used interchangeably in everyday speech, they have specific meanings in a scientific discussion.
Multiplication or division
Derived units areformed by combining the seven base units with (blank) or (blank). For example, speeds are typically expressed in units of metersper second (m/s).
Meter (M) KG Second (s)
The base units of length, mass, and time are the (blank), (blank), and (blank), respectively. In most measurements, these units will be abbreviated as (blank), (blank) & (blank)
unit Units Sec, hours, years
The description of how much of a physical quantity is represented by a certain numerical measurement and by the (blank) with which the quantity is measured. Although each dimension is unique, a dimension can be measured using different (blank). For example, the dimension of time can be measured in (blanks), (blank) or (blank).
Dimension
The description of what kind of physical quantity is represented by a certain measurement is called (blank).
Sig figs
The figures that are significant are the ones that are known for certain, as well as the first digit that is uncertain.
normal distribution Outlier
This data set appears as an approximately (blank), which results in a roughly bell-shaped curve, with most of the data points falling within one or two standard deviations of the mean. Notice that one of the data points is far away from the mean and is not within the standard-deviation zones. This data point is an (blank) and likely indicates an error in measurement.
Least
When addition or subtraction is the type of calculation, round the answer to the same amount of decimal places as the number in the equation with the (Blank) number of decimal places
7
When scientists do research, they must communicate the results of their experiments with each other and agree on a system of units for their measurements. In 1960, an international committee agreed on a system of standards, such as the standard shown in Figure 2.1. They also agreed on designations for the fundamental quantities needed for measurements. The system of units is called Systeme International d' Unites (SI). In SI, there are only (blank) base units. Each unit describes a single dimension, such as length, mass or time.
