methods from hypothesis. defining variables variables independent variable – what you change...

Methods from Hypothesis

Defining variables

Variables• Independent Variable

– What you change

• Dependent variable– The result you measure

• Control Variable– Everything that you keep the

same

• ONLY ONE– Independent Variable– Dependent Variable

What are the variables for the following hypotheses…• The strength of concrete depends

on the amount of sand, cement and aggregate present.

• Smarties melt at different speeds in the sun depending on their colour

• The speed that oil and water separate depends on the amount of emulsifier present

• The speed that marble chips react with Hydrochloric acid depends on the size of the marble chips

What you are going to do today

• You are going to research your hypothesis and complete your ISA “candidate research sheets” with a method so that someone else could fully investigate your hypothesis.

• In your ISA, you will be using your research sheet to carry out this practical.

• You can use ANY equipment or chemicals that you need. Marks are awarded for safety and fair testing.

Viscosity of Oil

Hypothesis• The viscosity of oil depends on the temperature

of the oil.– Viscosity = the thickness of the liquid.

Context• Oil in engines needs to be viscous enough to

move around the engine at different and high temperatures.