Classifying Matter
When a student drops different materials into water, what can they learn by watching which ones sink or float?
The density of each object
A student adds salt to water and stirs. How do we know that a solution was formed?
One substance dissolves in another, the mixture looks clear
If an object’s position changes compared to another object, the object is —
In motion
What form of energy allows a toaster to heat bread?
Electrical
Why should only one variable be changed in an investigation?
A) To make the experiment go faster
B) To see which variable caused the results
C) To make it easier to graph
To see which variable caused the results
A student places rubber, plastic, and wood pieces together. Which property would best explain how the materials were grouped?
Ability to insulate electricity
How can a student separate salt that has dissolved in water?
Let the water evaporate or Boil it
Which situation shows an unbalanced force?
A)A soccer player kicking a ball across the field
B) A ball sitting still on the floor
A soccer player kicking a ball across the field
Which example shows electrical energy being changed into motion energy?
A) A lamp lighting up
B) A fan spinning
A fan spinning
A student wants to test which brand of paper towel absorbs the most water. What is the dependent variable?
A) The amount of water absorbed
B) The brand of paper towel
C) The size of the container
The amount of water absorbed
A student adds sugar to warm water and stirs. The sugar disappears, What property stays the same?
Mass, Texture, or size?
The mass
What is true about the substances in a mixture?
They can be separated physically
What effect will increasing friction have on a moving object?
It will slow down or stop
What is the energy transformation when a doorbell rings?
Electrical → Sound
When analyzing results, what should students do to make sure their data is reliable?
A) Test only one time
B) Record only results that match the hypothesis
C) Repeat the investigation and average the results
Repeat the investigation and average the results
True or false: Rubber, glass, iron and Wood are all insulators.
False, iron is a conductor.
When two substances are mixed together and one disappears but the total mass stays the same, what kind of change occurred?
Physical Change
What is the difference between Energy Transfer vs Energy Transformation?
Energy Transfer: the same energy moves to another object
Energy Transformation: energy changes form