Working as a physicist

Question 1

What is the SI prefix for 10^15?

Answer 1

Peta

Question 2

What is the SI prefix for 10^12?

Answer 2

Terra

Question 3

What is the SI prefix for 10^9?

Answer 3

Giga

Question 4

What is the SI prefix for 10^6?

Answer 4

Mega

Question 5

What is the SI prefix for 10^3?

Answer 5

Kilo

Question 6

What is the SI prefix for 10^-3?

Answer 6

Milli

Question 7

What is the SI prefix for 10^-6?

Answer 7

Micro

Question 8

What is the SI prefix for 10^-9?

Answer 8

Nano

Question 9

What is the SI prefix for 10^-12?

Answer 9

Pico

Question 10

What is the SI prefix for 10^-15?

Answer 10

Femto

Question 11

What is the difference between independent and dependent variables?

Answer 11

● Independent variables are what you change in an investigation. Dependent variables are what is observed or measured.

● Independent variables are normally the cause of the effect on the dependent variables.

Question 12

Define Precision.

Answer 12

●A measure of how little spread there is in a set of data about a mean value.

●Precision does not indicate how close results are to the true value or if there was a systematic error.

Question 13

Define Accuracy.

Answer 13

A measure of how close a set of data is to the true value

Question 14

What is Random Error?

Answer 14

A single, isolated piece of data that doesn’t match the pattern from other data; should be omitted from results.

Question 15

What is Systematic Error?

Answer 15

A full set of data that doesn’t match the expected values; indicates a consistent fault with equipment or procedure.

Question 16

Define Repeatable/Reproducible.

Answer 16

An experiment that can be repeated to produce identical results

Question 17

How can the validity of results be improved?

Answer 17

● Control more variables
● Use more precise measuring
equipment
● Obtain more results to reduce
uncertainty

Question 18

Define error.

Answer 18

Error is the difference between the measurement and the true value.

Question 19

What is uncertainty?

Answer 19

Uncertainty is the interval within which the true value can be considered to lie with a given level of probability. It is determined by apparatus and variables.

Question 20

Define percentage uncertainty.

Answer 20

A percentage uncertainty is an uncertainty given as a ratio between the measured value and its difference to the true value.

Question 21

Equation for percentage uncertainty from a measurement

Answer 21

(absolute uncertainty / (mean) measured value) x 100 %

Question 22

Define absolute uncertainty.

Answer 22

An absolute uncertainty is the maximum possible difference between between a measured value and the true value value.

Question 23

Equation for absolute Uncertainty from a repeated Measurement

Answer 23

absolute uncertainty = (maximum measured value - minimum measured value) / 2

Question 24

What happens to the absolute
uncertainty when you
Add/Subtract/Multiply by a
Constant/Raise to a Power sets of data?

Answer 24

• ADD AND SUBTRACT: you add the absolute uncertainties together
• MULTIPLY: you multiply the absolute uncertainty by the constant
• RAISE: you raise the absolute uncertainty to the same power

Question 25

What happens to the % uncertainty when you ADD/SUBTRACT/MULTIPLY BY A CONSTANT/RAISE TO A POWER sets of data?

Answer 25

* ADD AND SUBTRACT: add together * MULTIPLY: doesn’t change * RAISE TO A POWER: multiply by the index