Practical Skills

Question 1

Name the 7 SI units

Answer 1

Meters m
Seconds s
Kilograms kg
Kelvins k
Amps A
Mole Mol
Candela cd

Question 2

Tera as a power of 10

Answer 2

10^12

Question 3

Giga as a power of 10

Answer 3

10^9

Question 4

Mega as a power of 10

Answer 4

10^6

Question 5

Kilo as a power of 10

Answer 5

10^3

Question 6

Centi as a power of 10

Answer 6

10^-2

Question 7

Milli as a power of 10

Answer 7

10^-3

Question 8

Micro as a power of 10

Answer 8

10^-6

Question 9

Nano as a power of 10

Answer 9

10^-9

Question 10

Pico as a power of 10

Answer 10

10^-12

Question 11

Femto as a power of 10

Answer 11

10^-15

Question 12

Independent variable

Answer 12

What you’re in charge of changing

Question 13

Dependent variable

Answer 13

What you measure

Question 14

Control variables

Answer 14

What you keep the same

Question 15

1st step of experiment planning

Answer 15

Find an equation that answers the question

Question 16

2nd step of experiment planning

Answer 16

Decide what needs to be measured

Question 17

3rd step of experiment planning

Answer 17

Decide what equipment will be precise

Question 18

4th step of experiment planning

Answer 18

Decide independent dependant and control variables

Question 19

5th step of experiment planning

Answer 19

Draw a diagram to show how equipment should be set up

Question 20

6th step of experiment planning

Answer 20

Test the largest and smallest values you can get from Independant variable

Question 21

7th step of experiment planning

Answer 21

Write method

Question 22

Experiment design steps summary

Answer 22

-Make hypothesis/prediction
-Decide what data to collect/how
-Find Independant dependant and control variables
-Select appropriate equipment
-Risk assessment

Question 23

Hazard

Answer 23

Anything that can cause harm

Question 24

Risk

Answer 24

How someone could be harmed by a hazard

Question 25

Prevention

Answer 25

How to stop someone being harmed

Question 26

What does a full rotation on a micrometer mean

Answer 26

A 1/2 mm line on main scale

Question 27

What's on the micrometer rotating scale

Answer 27

50 divisions each 0.01 mm

Question 28

How to read micrometer

Answer 28

1)Look what line has just been uncovered on main scale 2)See what number rotating scale lines up with on main scale 3)Add main and rotating scale together

Question 29

Advantage of micrometer

Answer 29

-They are all the same -Can't overtighten and squash due to ratchet -More precise (0.01mm rotating scale)

Question 30

Vernier calliper advantages

Answer 30

-Upper jaws to measure internal diameter

Question 31

How to read vernier callipers

Answer 31

-Look for 0 -Vernier scale= zoomed version of 1mm. 1mm÷increments -Look where line on main scale matches vernier scale -Add this to main scale reading

Question 32

Tables rules

Answer 32

-Units separated from quantity with / -Independant variable on left -Record all data and averages to the same DECIMAL places -Calculated data should be rounded to lowest number of significant figures

Question 33

Graph rules

Answer 33

-Fill grid -Axis doesn't need to start at 0 -Line/curve of best fit -Don't join dots -Label axis -Circle obvious anomalies

Question 34

How to do error bars

Answer 34

Calculate mean value. Calculate range Divide range by 2 for absolute uncertainty Absolute uncertainty above and below mean

Question 35

Systematic error

Answer 35

Errors that affect all measurements by the same amount

Question 36

Example of systematic error

Answer 36

A balance that reads already 0.4g and this is added to each measurement

Question 37

How to reduce systematic errors

Answer 37

Reduce effects by calibrating equipment

Question 38

Random error definition

Answer 38

An error that affects all measurements bt different amounts

Question 39

Example of random error

Answer 39

Human reaction time with a stopwatch

Question 40

How to reduce random error

Answer 40

Reduce effects by taking repeat readings so you can spot and remove anomalies Take an average to smooth out results

Question 41

Parallax error definition

Answer 41

-Type of random error -Caused by eye, object measured and measuring device. -Eliminate using set square or place object directly under measuring device

Question 42

Calibration error

Answer 42

-Type of systematic error -Caused when you don't check equipment is reading 0 when it should be -Check it reads 0 or measure something of known size

Question 43

What is the uncertainty in a reading +example of equipment

Answer 43

Where you look at equipment once to make judgement Eg: thermometer, cylinder, geuger ±1/2 the smallest division

Question 44

What is uncertainty in a measurement +Example of equipment

Answer 44

Where you look at equipment twice to make a judgement. Eg: Calliper, protracter, ruler ±1 the smallest division

Question 45

Uncertainty in digital meters +example of equipment

Answer 45

Eg: stopwatch, voltmeter ±1 the smallest division

Question 46

Uncertainty in exam data

Answer 46

Assume ± in the last significant digit

Question 47

How to calculate percentage uncertainty

Answer 47

(Absolute uncertainty÷reading) x100

Question 48

How to calculate uncertainty when adding 2 measurements

Answer 48

Add absolute uncertainties

Question 49

How to calculate uncertainty when subtracting 2 measurements

Answer 49

Add absulute uncertainties

Question 50

How to calculate uncertainty when multiplying 2 digits

Answer 50

Add percentage uncertainties

Question 51

How to calculate uncertainty when dividing 2 digits

Answer 51

Add percentage uncertainties

Question 52

How to calculate uncertainty when you raise a value to a power

Answer 52

Multiply uncertainty by the power

Question 53

If you measure thickness of a coin by finding thickness of stack of 10 and then dividing that by 10 what happens to % uncertainty?

Answer 53

Stays the same

Question 54

How to calculate uncertainty from a range of results

Answer 54

Find range Divide range by 2 for absolute Find mean (Absolute÷mean) x100

Question 55

Precise result

Answer 55

Small spread in the data from the mean

Question 56

Repeatable result

Answer 56

If you can repeat the experiment multiple times and get the same results

Question 57

Reproducible result

Answer 57

If someone else can recreate the experiment using different equipment and methods and get the same results

Question 58

Accurate result

Answer 58

Close to true value

Question 59

If percentage difference is smaller than percentage uncertainty

Answer 59

Theory is supported by the results

Question 60

Theory is supported by results

Answer 60

If percentage difference is smaller than percentage uncertainty

Question 61

If percentage difference is bigger than percentage uncertainty

Answer 61

Theory is not supported by results

Question 62

Theory is not supported by results

Answer 62

If percentage difference is bigger than percentage uncertainty