Practical Skills Flashcards
(26 cards)
Independent
Dependent
Control
Independent - what you are changing
Dependent - what you are measuring
Control - what you keep the same
How to measure uncertainty (use themometer as example)
- measuring temperature
- this is a reading
- if smallest division is 1 degree (the scale) then the uncertainty will be half the smallest division which is 0.5 degrees
- both uncertainties and numerical values must be to the same decimal places so it will read 1.0 degree +- 0.5 degrees
- Measuring temperature difference
- this is a measurement
- again apply the smallest division here, however uncertianty will be times by two as there will be uncertainty in each reading hence it is 1 degrees +- 1 degrees
How do you calculate uncertianty here
Find range and then divide range by 2
Use ruler and make it perpendicular to the lines. Place set square along the ruler to prove they are parallel
Describe a suitable procedure to measure y
Place a metre ruler vertical against the end of the steel tape. Use a level to make sure it is vertical. Calculate at eye level values A and B and to calculate y, y = A - B
What must your answer b if answer is an integer
A Whole Number
Y = Ax^n Y and X have units cm, and n = 4
a) what is the units of A
b) if A = 3 x 10^-7 what is the order of magnitude of A
a) cm^-3
b) order = -7 / 10^-7
Difference between precision and accuracy
37.8
All uncertainties you need to know
How to calculate uncertainties in gradients
