What is the difference between an observation and an inference?
An observation is something you notice with your senses or tools. An inference is a conclusion based on observations.
What are the three common states of matter?
Solid, Liquid, Gas
What equation is used to calculate speed?
Speed = Distance ÷ Time
What is a force?
A push or a pull.
What force pulls objects toward Earth?
Gravity
What is the independent variable?
The variable that is changed by the scientist.
Name the three subatomic particles.
Protons, Neutrons, Electrons
A runner travels 100 meters in 20 seconds.
What is the runner's speed?
100 ÷ 20 = 5 m/s
Balanced forces cause what change in motion?
No change in motion.
What is kinetic energy?
Energy in motion
A scientist wants to know if fertilizer affects plant height.
What is the:
Independent variable?
Dependent variable?
IV: Amount/type of fertilizer
DV: Plant height
What is the difference between a physical change and a chemical change?
A physical change does not create a new substance. A chemical change creates a new substance.
A bicycle travels at 8 m/s east.
What is its velocity?
8 m/s east
Which Newton's Law says objects stay at rest or stay in motion unless acted upon by an unbalanced force?
Newton's First Law
What is potential energy?
Stored energy because of an object's position.
What are the three parts of CER?
Claim, Evidence, and Reasoning
An object has:
Mass = 60 g
Volume = 20 cm³
What is its density?
60 ÷ 20 = 3 g/cm³
A car travels 360 km in 6 hours.
What is its average speed?
360 ÷ 6 = 60 km/h
A shopping cart is difficult to push when it is full.
Which Newton's Law explains this?
Newton's Second Law
(More mass requires more force.)
A book sits on the top shelf of a bookcase.
What type of energy does it mostly have?
Potential energy
A scientist changes the amount of sunlight each plant receives but also changes how much water each plant gets.
Why is this NOT a fair test?
More than one variable changed, so the scientist cannot determine which variable caused the results.
A cube has a density of 0.75 g/cm³.
It is placed into water.
Will it sink or float? Explain why.
It floats because it is less dense than water (1.0 g/cm³).
Two students race.
Student A travels 90 meters in 15 seconds.
Student B travels 120 meters in 20 seconds.
Who is faster?
They traveled at the same speed.
A rocket launches into space.
The rocket pushes gases downward.
What pushes the rocket upward?
Which law explains this?
The gases push back on the rocket.
Newton's Third Law.
A roller coaster begins at the top of a hill.
As it rolls downhill:
What happens to its potential energy?
What happens to its kinetic energy?
Why?
Potential energy decreases.
Kinetic energy increases.
Gravity causes stored potential energy to transform into kinetic energy as the coaster speeds up.