Practical Skills & Foundations Of Physics

Question 1

Absolute uncertainties

Answer 1

Interval that a value is said to lie within, with a given level of confidence

Question 2

Accuracy

Answer 2

A measure of how close a measurement is to the true value

Question 3

Analogue apparatus

Answer 3

Measuring apparatuses such as rulers, beakers and thermometers that rely on the experimenter reading off a scale to determine the measurement

Question 4

Anomalies

Answer 4

Data points that don’t fit the pattern of the data
Determine why an anomalous result has occurred before removing it
Repeat readings help remove anomalies

Question 5

Control variables

Answer 5

Variables that must remain the same throughout an experiment so as to not affect the results

Question 6

Dependent variables

Answer 6

The variable being measure in an experiment
Dependent on the independent variable
Plotted on the y axis of a graph

Question 7

Digital apparatus

Answer 7

Measuring apparatuses such as ammeters, voltmeters and digital callipers that digitally measure and display a measurement

Question 8

Fiduciary marker

Answer 8

A thin marker, such as a splint, that is used to ensure readings are taken from the same place each time
Improve accuracy of measurements

Question 9

Gradient

Answer 9

Change in y value over change in x value between two points
If the graph is curved, a tangent can be drawn to calculate the gradient at a specific point

Question 10

Independent variables

Answer 10

Variable changed by the experimenter in an experiment
Plotted on the on the x axis

Question 11

Line of best fit

Answer 11

A line drawn on a graph to demonstrate the pattern in the plotted data points

Question 12

Percentage uncertainties

Answer 12

The uncertainty of a measurement, express as a percentage of the recorded value

Question 13

Precision

Answer 13

A measure of how close a measurement is to the mean value
Only gives an indication of the magnitude of random errors, not how close data is to the true value

Question 14

Prefixes

Answer 14

Added to the front of units to represent a power of ten change

Question 15

Random errors

Answer 15

Unpredictable variation between measurements that leads to a spread if values about the true value
Random error can be reduced by taking repeat me@urementa

Question 16

Repeatable

Answer 16

The same experimenter can repeat a measurement using the same method and equipment and obtain the same value

Question 17

Reproducible

Answer 17

An experiment can be repeated by a different experimenter using a different method and different apparatus and still obtain the same results

Question 18

Resolution

Answer 18

The smallest change in quantity that causes a visible change in the reading that a measuring instrument records

Question 19

Resolution forces

Answer 19

The splitting of a forced into its horizontal and vertical components

Question 20

Scalar quantities

Answer 20

A quantity that only has a magnitude, without an associated direction
Speed, distance, temperature

Question 21

SI units

Answer 21

The standard units used in equations
International standard of units- physical quantities and units
Metres, kilograms, seconds, amps, kelvin, moles

Question 22

Significant figures

Answer 22

A measure of a measurement’s resolution
All numbers except zero we counted as a sig fig
When zeros are found immediately after a dcimal place they too are counted

Question 23

Systematic errors

Answer 23

Causes all readings to differ from the true value by a fixed amount
Cannot by corrected by repeat readings, instead a different technique or apparatus should be used

Question 24

Triangle of forces

Answer 24

A method of finding the resultant force of two forces
Two forces joined up tip to tail and the result is then the vector that completes the triangle

Question 25

Vector quantities

Answer 25

A quantity that has both a magnitude and an associated direction
Velocity, displacement, acceleration

Question 26

Vernier scales

Answer 26

The type of scale used on callipers and micrometers, that involve reading from a fixed scale and a moving scale to produce accurate measurements

Question 27

Zero errors

Answer 27

A form of systematic error, caused when a measuring instrument doesn’t read zero at a value of zero
Results in all measurements being offset by a fixed amount