Skip to content | Accessibility - list of access keys used on this site | Sitemap
Find what you need to know

Home > Subjects > Physics > Level 2 > 2.1 Physics investigation > Key tips

  • Subject: Physics
  • AS: 91168
  • Level: 2
  • Credits: 4
  • Internal

Physics 2.1 Carry out a practical physics investigation that leads to a non-linear mathematical relationship

Key tips

Follow the written instructions that will be given to you by your teacher.

Ask lots of questions.

If you draw a raw-data graph, make sure you can recognise from the shape of the graph the four types of relationships (linear, square, inverse, and inverse square).

You will be provided with a formula for the relationship between the variables.  Use this to help decide the type of relationship and which transformations will give you a straight line graph.  For example if you are investigating the relationship between the distance travelled by an accelerating object, and the time since it was at rest, the relevant formula is d= ½at2 .  So a graph of ‘d’ against ‘t2’ will produce a straight line with a gradient of ½a. 

Make sure you prepare for the assessment by knowing how to transform data from a non-linear relationship to give a straight-line graph.

Draw a careful and accurate straight-line graph with both axes carefully labelled with quantity and unit.  Don’t forget to transform your units.  For example, if one of your graphed variables is time squared (t2) then the units for that axis will seconds squared (s2).  The axis label will look like this: t2(s2). 

Draw a Line of best fit (LOBF) and use it to work out the gradient.  Be careful to use the line, not your data table, to find the gradient.  Show how you worked out the gradient by drawing a triangle on the LOBF.

The units of the gradient are the units of the ‘y’ axis over the units of the ‘x’ axis. For example, a graph of distance against time-squared will have units m/s2 or ms-2.

Give the mathematical relationship in terms of the actual variables, not ‘y’ and ‘x’.  For example a graph of ‘d’ against ‘t2’ with a gradient of 5.1 gives a relationship d=5.1t2

You can use your relationship to work out a value for a physical quantity or constant.  For example a relationship of d=5.1t2 can be equated with the provided formula d= ½at2 to give a=10.2ms-1.

Back to top


People logged in


People surfing this site

Most recent posts

English Level 1
How to please your teacher with your formal writing

Posted by: Future Engineer

5:34pm 19.07.2014

English Level 2
Should i practice with the poem?

Posted by: Future Engineer

5:45pm 20.07.2014

English Level 3 & Scholarship
3.2 (91473) VISUAL TEXTS post all your essays/Qs here

Posted by: rainydays789

6:51pm 14.07.2014

Mathematics Level 1
Algebra and graphs (91027, 91028, 91029)

Posted by: mathsteacher

10:53pm 21.07.2014

Mathematics Level 2
Algebra (91261, 91269)

Posted by: mathsteacher

5:26pm 07.07.2014

Mathematics Level 3 Calculus & Calculus Scholarship
Parametric Equations of a parabola and value of 'a'

Posted by: SandmanNZ123

11:39pm 22.07.2014

Mathematics Level 3 Statistics & Statistics Scholarship
3.10 (AS91582) Inference

Posted by: Kiaorahi

9:18pm 29.05.2014

Sciences Level 1

Posted by: Future Engineer

8:41am 26.05.2014

Science Level 2 & 3

Posted by: Doo

9:26pm 17.11.2013

Physics Level 2

Posted by: Future Engineer

9:09am 03.06.2014

Physics Level 3 & Scholarship

Posted by: Future Engineer

5:40pm 22.07.2014

Biology Level 2, 3 & Scholarship
3.2 Socio-scientific issue AS 91602 Internal

Posted by: scienceteacher5

7:22am 20.07.2014

Chemistry Level 2, 3 & Scholarship
Chemistry Olympiad

Posted by: Future Engineer

5:30pm 09.07.2014

Physics website for Levels 1, 2, and 3

Posted by: Future Engineer

6:23pm 19.07.2014