Measurements And Errors

Question 1

What is the prefix factor of pico?

Answer 1

10^-12

Question 2

What is the prefix factor for Tera

Answer 2

10^12

Question 3

Prefix factor of Giga?

Answer 3

10^9

Question 4

What is bigger deci or centi?

Answer 4

Deci because it is 10^-1 and centi is 10^-2

Question 5

Millimetre is M or m

Answer 5

m

Question 6

What is the derived unit of frequency?

Answer 6

Hz (Hertz)

Question 7

What is the equation of frequency?

Answer 7

1/T

Question 8

What is the base unit of frequency?

Answer 8

1/s or s^-1

Question 9

What is the equation of pressure?

Answer 9

Force/Area

Question 10

What is the derived unit of pressure?

Answer 10

Pa (Pascals)

Question 11

What is the base unit of pressure?

Answer 11

Kgm^-1s^-2

Question 12

Is the base unit for mass kg or g

Answer 12

Kg

Question 13

Is the base unit for length m or cm

Answer 13

m

Question 14

What is the derived unit for work and energy?

Answer 14

Joules

Question 15

What is the base unit for kinetic energy?

Answer 15

Kgm^2s^-2

Question 16

Base unit for velocity squared?

Answer 16

m^2s^-2

Question 17

Base unit for acceleration?

Answer 17

ms^-2

Question 18

What does homogeneous equations mean?

Answer 18

Units on the left side of the equation are the same as the right

Question 19

What does precision mean?

Answer 19

How close the results are to eachother

Question 20

What does accuracy mean?

Answer 20

How close the results are to the real value

Question 21

Real value : 3.25

Experimental values : 4.12 4.11 4.13

Are these values precise or accurate?

Answer 21

Precise but low accuracy

Question 22

What is random error?

Answer 22

A statistical error that is unpredictable and affects the measurements

Question 23

Can random errors be controlled?

Answer 23

No because they are unpredictable

Question 24

Give an example of a random error

Answer 24

Environment

Change in mass

Not reading equipment efficiently - parallax error

Question 25

What is systematic error

Answer 25

An error that effects all the variables in the same way

Question 26

Which error affects the gradient?

Answer 26

Random

Question 27

Give an example of systematic error

Answer 27

Zero error - when what is being measured doesn’t start at 0

Question 28

Give an example of systematic error

Answer 28

Zero error - when the what is being measured doesn’t start at 0

Question 29

How do you work out absolute uncertainty?

Answer 29

Half the range

Question 30

What is the absolute uncertainty of a device?

Answer 30

The smallest reading/scale on the device

Question 31

What is the Absolute uncertainty of a 15cm ruler with the smallest reading of 1mm

Answer 31

0.15m +- 0.001m

Question 32

What is the uncertainty of 7.89kg

Answer 32

0.01kg

Question 33

What is the uncertainty of 4.63748 V

Answer 33

0.00001V

Question 34

How do you work out % uncertainty?

Answer 34

Uncertainty —————— x100 Value

Question 35

When combining uncertainties do you add or subtract

Answer 35

Add NEVER subtract

Question 36

When adding or subtracting quantities what do you do first?

Answer 36

Add the absolute uncertainties first

Question 37

When multiplying or dividing quantities what do you do first?

Answer 37

Add the percentage uncertainties first

Question 38

How do you work out the uncertainty of a quantity raised to the power?

Answer 38

Multiply the power by the % uncertainty

Question 39

What do error bars show?

Answer 39

Absolute uncertainty

Question 40

How do you work out the %U of a gradient?

Answer 40

Best gradient - worst gradient _______________________________. X100 Best gradient

Question 41

How do you reduce random errors?

Answer 41

By taking multiple measurement and averaging the result

Question 42

How do you reduce systematic error?

Answer 42

Calibrate the equipment Conduct experiment in a stable environment Warm up instruments Eliminate zero error

Question 43

Repeatable experiment

Answer 43

The **same** person repeats the experiment and obtains the same result

Question 44

Reproducible experiment

Answer 44

An experiment repeated by a **different person** and different equipment and obtain the same result

Question 45

Resolution

Answer 45

The smallest change in quantity on a measuring equipment that causes a noticeable change in reading

Question 46

How do you work out an uncertainty with a constant?

Answer 46

Multiply the absolute uncertainty by the constant

Question 47

What is a reading?

Answer 47

When one value is found

Question 48

What is a measurement?

Answer 48

The difference between two readings

Question 49

How do you work out the uncertainty of a reading?

Answer 49

Half the smallest division