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SEMESTER 1 PHYSICAL SCIENCE FINAL STUDY GUIDE
Science Process Skills
Know these vocabulary words and be able to use them to answer higher level questions about
experiments and data collection:
What do we study in physical science? Chemistry and Physics
What is matter? The amount of mass that makes up an object
What is energy? The ability to do work and cause change
What is the Scientific Method? Scientists are filled with curiosity and ask many questions
about our world and our universe. They use the problem solving process called the
scientific method to investigate and find answers to their questions.
What is an independent variable in an experiment? The variable in an experiment that is
changed on purpose by the scientist. The factor that “I” (the scientist) choose to change
or manipulate for an experiment.
What is a dependent variable in an experiment? The variable that responds to changes in the
independent variable in an experiment. The variable you will measure and collect data on
during an experiment.
What is a manipulated variable in an experiment? The Independent Variable
What is a responding variable in an experiment? The Dependent Variable
What are the constant conditions in an experiment? All the variables in an experiment that
the scientist decides will remain exactly the same for the whole experiment.
What is the Non-Treated/Control Group in an experiment? The item or group in an
experiment that remains unchanged or does not include the independent variable. This
group is used as comparison for checking the results of an experiment and gives you
evidence to draw conclusions about your independent and dependent variables.
What are qualitative observations? Observations made during an experiment that involve the
senses (hearing, seeing, tasting, smelling, touching). These are descriptions of what we
observe about the conditions in the experiment.
What are quantitative observations? Observations made during an experiment that involve
numbers or amounts. These are measurements of what we observe.
What is the hypothesis in an experiment? A statement that offers an answer to a testable
question that has been asked. It is written in the form:
If (the independent variable) is (increased, decreased, changed),
then (the dependent variable) will (increase, decrease, change)
because (use prior knowledge, observations, inferences).
What is the conclusion in an experiment? You use data and evidence from an experiment and
then you analyze the data and explain how this answers your original testable question.
What is the difference between an observation and an inference? An observation is anything
we become aware of through one or more of our senses. While an inference is an
explanation based on your observations. Inferences are not about being correct or not.
Inferences should be logical. Inferences can be changed when new observations are made.
Inferences use observations and prior knowledge to explain what happened in the past.
Why don’t we have one single scientific method that every scientist must use each time an
experiment is conducted? The names of the steps can vary but usually involve a problem,
formulating a hypothesis, making observations, collecting and analyzing data, and logical
reasoning for drawing conclusions. The scientific method is just a guideline that we use in
science. The steps can be changed or adapted to meet your specific experiment or
investigation.
What are the steps of the scientific method we are using this year?
Step 1-State the Problem: Ask a Testable Question
How does. . .?, What does. . .?, Which. . .?, How can. . .?, What can. . . ?
Step 2-Collect Background Information: Research information that will help you answer the
testable question. Use books, articles, the Internet, and your own experience. Has this been
done before? Do you have background knowledge of the science topics?
Step 3-Invent a Hypothesis: Propose an answer to the testable question based on the
background information you collected. State the hypothesis as a cause-effect relationship. Put
it in an “If (independent variable), then (dependent variable) because. . .” statement.
Step 4-Experiment: Record materials and equipment used; Be sure to take safety into
account; Record your procedure (step by step process); Record the variables(s) that are being
measured, manipulated and controlled. Could someone else read and follow your procedure and
repeat your experiment?
Step 5-Note Data: Create data tables so collected data is organized and easy to read; Make
graphs using the collected data; Independent variable on x-axis and dependent variable on yaxis ; Look for patterns and relationships between the variables
Step 6-Conclusion: State the purpose of the experiment; Summarize the data collected and
include any trends or patterns you discovered; Report if the data supports, partially supports,
or does not support your hypothesis; Think about what changes could be made if the experiment
were conducted again.
Step 7-Educate Others: Inform others of the results and conclusions so investigations can be
repeated
Explain what occurs in each step of the scientific method See answer in question above
Be able to pick out the independent variable, dependent variable, constant conditions/constants,
control group/non-treated group if given an experiment scenario –
Look over your Science Process Skills Test
Why we do multiple trials for experiments? To make sure our experimental results were not
flawed.
Be able to analyze a data table and a graph to draw a conclusion about an experiment
Look over your Science Process Skills Test and your data table and graphing notes
Know your science safety rules Look over your Safety Test
What is a scientific law? An explanation of what is observed in the natural world. A law
describes a pattern seen in the natural world. A law can be used to predict what will
happen in a given situation, but it will not explain why it happens.
What is a scientific theory? A well-established explanation for how or why a phenomenon
happens in our natural world. The explanation is based on large amounts of data and
observations that are supported by experimental results that have been proven multiple
times. Scientific theories can explain scientific laws.
Motion-Speed, Velocity, and Acceleration
What is the position of a person or object? Where an object is located
What is motion? Motion is an object’s change in position over time when compared with a
reference point. An object is in motion if its distance from another object changes.
What is a reference point? A reference point is an object that is used for comparison to
determine if other objects are in motion.
What is distance? The amount that an object is away from a reference point. (Include its
units)
What is displacement? The amount that an object is away from a reference point including
its units AND the direction away from the reference point.
What is speed? Speed is a type of rate that gives the distance an object travels in a given
time. It is how fast an object is moving.
Speed = Distance Traveled
Time to Travel Distance
What is velocity? Velocity is how fast an object is traveling and the direction it is
traveling.
Velocity = Distance Traveled in a direction
Time to Travel Distance
How are speed and velocity different? Velocity is the speed of an object with its direction
What is average speed and average velocity? Average speed is the overall distance an object
travels divided by the total time it took to travel the distance because most moving
objects do not move at a constant speed. Average velocity is the same as average speed
but it includes the direction.
Average Speed = Total Distance
Total Time
Average Velocity = Total Distance in a direction
Total Time
What is constant speed and constant velocity? Constant speed is the speed of an object when
the speed is the same at every point of its motion. Ex. Using Cruise Control
Constant velocity is when an object is traveling at a constant speed and there is no change
in the direction of the motion.
What is instantaneous speed? The rate an object is moving at a given instant in time.
What is acceleration? The rate at which an object’s velocity is changing. An acceleration
of an object occurs if there is any change in velocity, either its speed or direction.
Acceleration = Final Velocity-Initial Velocity
Time to Change Velocity
= vf – vi
t
Be able to explain what type of acceleration is going on in a given situation:
(1) Speeding Up-Increasing Speed which is called positive acceleration
(2) Decreasing Speed which is called negative acceleration or deceleration
(3) Change in Direction-Ex. Circular Motion
Be able to read and analyze Distance vs Time and Speed vs Time Graphs
Look at the questions on graphing on your Motion Test and at your Motion Graphs Note
Packet
What kind of motion graph represents the speed of an object? Distance vs Time Graphs
What kind of motion graph represents the acceleration of an object? Speed vs Time Graphs
Know the equations for Speed, Velocity, Average Speed, Average Velocity, Acceleration –
See questions above
Be able to use the correct units when solving any equation or word problem related to motionSpeed, Average Speed – ex. m/s, mi/h, km/h
Velocity, Average Velocity – ex. m/s, mi/h, km/h + a direction
Acceleration – ex. m/s2, mi/h2, km/h/s + a direction
Forces
What is a force? A push or pull in a particular direction.
What is a balanced force? Two or more forces are balanced if there effects cancel each
other out and they do not cause a change in an object’s motion (If the object is stopped,
it remains stopped and if the object is already moving then it keeps moving at the same
speed and in the same direction.)
What is an unbalanced force? Two or more forces are unbalanced if there effects do not
cancel each other out because one force is stronger than the other. Unbalanced forces do
cause a change in an object’s motion either speed and/or direction.
What is the net force? The total of all the forces acting on an object.
What is a spring scale used for? A spring scale is used to measure the force that a push or
pull is exerting on an object.
What is a newton (N)? The unit used to measure a force. It is equal to kg●m/s2.
What is friction? Friction is a force that is caused by the surface roughness when 2
objects are in contact. Friction always acts in the direction opposite of the motion of the
object and causes moving objects to slow down or stop.
Is friction a force? Yes, friction is a force that opposes motion.
What 2 factors determine the amount of friction between two objects?
(1) Types of surfaces involved and
(2) How hard the surfaces push together due to the force of each object
How can friction be useful? Yes, whenever you need friction to make something happen. For
instance, we would not able to walk or hold things or open doors, etc. without friction.
How can friction be harmful? Friction creates heat which can damage equipment. Friction
causes wear to things like tires and brake pads on a car. Friction makes it difficult to
move objects especially if you are trying to slide heavy objects.
What are the 2 main types of friction? Define them.
1. Static Friction - Friction when a force is applied to an object, but it does not cause
the object to move. The static friction balances with the force applied so the object
does not move. Static friction disappears as soon as the object moves and it is
immediately replaced by another kind of friction.
2.Kinetic Friction - Friction of moving surfaces
What are the 3 types of kinetic friction? Define them.
Sliding Friction - Friction when solid surfaces slide over one another. Produces heat when
the two objects are rubbed together. Example – Rub your hands together quickly, Rubbing
sticks together to make a fire
Rolling Friction - Friction when an object rolls over a surface.
The force needed to overcome rolling friction is usually much less than that for sliding
friction.
Fluid Friction - Friction that occurs when an object moves through a fluid. Fluids include
liquids and gases. The force needed to overcome fluid friction is less than that needed to
overcome sliding friction.
Example – To prevent heat from building up in a car engine, oil is used to lubricate the
parts of the car engine so that it runs smoothly.
How can you change the strength of friction between two surfaces?
3 Ways of Reducing Friction
(1) Decrease the surface area between the things that are rubbing together by making
them smoother -Any extra lumps or bumps on an object increases its surface area so it
increases its friction. If you sand the object to make it smoother this will decrease the
friction.
(2) Use something to make the surfaces more slippery -Applying things like water, oil, or
grease to a surface will decrease the friction because they will fill in any tiny holes on the
surface.
(3) Switch from sliding friction to rolling friction
3 Ways of Increasing Friction – Do the opposite of the 3 things above
What is air resistance? A type of fluid friction that slows down objects falling through the
air or objects moving forward through air (like a car)
In what direction does friction always work? Opposite the motion of an object
What is gravity? Gravity is a type of force that pulls things together. It is a “together”
force, not a “down” force. On the Earth, the force of gravity is everywhere towards
Earth’s center.
Is gravity a force? Yes, gravity is a type of force that pulls objects toward the center of
an object.
What 2 factors determine the amount of gravity between two objects?
(1) The mass of each object involved
(2) The distance between the 2 objects
What is the Universal Law of Gravitation? The law that says that the force of gravity acts
between all objects in the universe.
What is projectile motion? Projectile motion is the curved path followed by an object when
it is thrown or propelled. It has 2 components – (1) Horizontal Motion and (2) Vertical
Motion but objects in projectile motion only accelerate downward or vertically so you
always need to aim above a target if you want to hit it with an object that is thrown or
propelled.
What is mass? Mass is the amount of matter or material that makes up an object.
What is weight? The force of attraction between an object and whatever planet it is on.
Each planet has a unique amount of gravity and you use that to multiple by the mass of an
amount to determine its weight. Weight is a force.
How much is the acceleration due to gravity on Earth? 9.8 m/s2
What is terminal velocity? Terminal velocity occurs for an object when the Force of Air
Resistance =Force of Gravity. As an object speeds up the air resistance also increases
until the 2 forces are equal and the object reaches its terminal velocity. If you have
balanced forces on an object then it no longer accelerates. If an object is not
accelerating it is still falling but the velocity and the direction are not changing.
What is weightlessness? Weightlessness occurs when an object is in free fall and is
experiencing less gravity. (It is not when there is no gravity.)
What kind of motion is involved when an object orbits? When an object is in orbit it
experiences forward motion and free fall.
For all the following ideas look over your old Forces Test
Be able to describe a force by its direction and magnitude
Be able to compare the effects of balanced and unbalanced forces on an object’s motion
Be able to explain that when forces are balanced then the objects must be at rest or
their motion remains constant
Be able to explain that a change in motion results from an unbalanced force acting on an object
Be able to recognize that all objects in the universe has a gravitational force of attraction on
every other object
Be able to recognize that an object’s weight is a measure of the gravitational force of a planet
or moon acting on an object
Be able to compare the amount of gravitational force acting between objects
(which depends on their mass and the distance between them)
Be able to compare and contrast mass and weight
Be able to determine which dropped objects will hit the ground first
NEWTON’S LAWS OF MOTION
What are Newton’s Three Laws of Motion?
Newton’s First Law of Motion:
An object at rest will remain at rest, or an object moving at a constant speed will continue
moving at that speed, unless acted upon by an unbalanced force.
Newton’s Second Law of Motion:
The amount that an object will be affected by a push or a pull is equal to the mass of the
object multiplied by the acceleration.
Newton’s Third Law of Motion:
For every action, there is an equal and opposite reaction. Therefore, if one object exerts
a force on a 2nd object, then the 2nd object exerts a force of equal strength in the
opposite direction of the force back on the 1st object.
What is inertia? Inertia is the tendency of anything with mass to resist a change in motion.
The greater the mass of an object, the greater its inertia.
How is the inertia of an object related to the mass of the object? The mass of an object
determines its inertia. The greater the mass of an object, then the greater the inertia.
What is the equation for Newton’s 2nd Law of Motion? Force = mass ● acceleration (F = m•a)
What is unit does this represent kg•m/s2? A newton (N)
What is an action force? The initial force from Object #1 onto Object #2.
What is a reaction force? The second force that goes from Object #2 onto Object #1.
What is momentum? Momentum is mass in motion so any moving object with mass has
momentum. Momentum depends on (1) how much stuff is moving and (2) how fast that
stuff is moving.
What is the equation for momentum? Momentum (P) = mass●velocity = m●v
What is the unit used of momentum? kg●m/s
What is the Law of Conservation of Momentum? The Law that says that momentum cannot
be created or destroyed.
How is the Law of Conservation of Momentum used to predict what happens in collisions?
When an object with momentum collides with another object, the momentum is
transferred. The total amount of momentum between two objects will add up to the same
amount when you add the momentum of each one together before the collision and after
the collision.
For all the following ideas look over your old Newton’s Laws section of your Forces Test
Be able to explain how Newton’s Laws of Motion apply to new situations
Be able to predict how Newton’s Laws affect moving objects
Be able to solve word problems for Newton’s 2nd Law of Motion
Be able to solve word problems for Momentum
ENERGY
What is kinetic energy? Energy of Motion that depends on both the mass of the object and
its velocity
What is potential energy? Stored energy
What is gravitational potential energy? Stored energy due to the position (where it is
located) of an object
What is elastic potential energy? Stored energy in the stretch of an object
Ex. Rubber Band or Slinky
How are kinetic and potential energy related? Kinetic and potential will always equal the
total energy of a system. The mechanical energy or total energy of an object due to its
motion and its stored energy.
How do you calculate kinetic energy?
KE = mass•velocity2
2
or
m•v2
2
How do you calculate potential energy? PE (or GPE) = Weight • Height (W●h) or =
mass●gravity●height (m●g●h) Remember that g = 9.8 m/s2
Can kinetic energy and potential energy be converted to one another? How do you know?
Yes because the total energy of the system must always it up to the same amount so when
potential energy goes up kinetic energy goes down and vice versa.
How do you calculate total mechanical energy?
Mechanical Energy = Potential Energy + Kinetic Energy
ME = PE + KE
How are energy and work related? Energy is the ability to do work or cause change. An
object with energy can change itself or cause change in other objects.
What are the units for energy? Joule (J) = N•m = kg•m2/s2
What is the Law of Conservation of Energy? Energy can never be lost, can never be created,
and can never be destroyed so energy can only change from one form to another form.
Can energy change from 1 form to another while the total energy remains the same?
Yes because this is the Law of Conservation of Energy.
Can energy be created or destroyed? Never
ENERGY CONVERSIONS
What is mechanical energy? All the energy in a system but it is often used to describe just
the kinetic energy.
What is thermal energy? It is also known as heat energy. Thermal Energy is a form of
Kinetic Energy. The faster the particles move, the more heat energy they have.
What is chemical energy? Energy that exists in the bonds between atoms and is released
when the bonds are broken. Chemical Energy is a form of Potential Energy.
What is radiant energy? Radiant energy is Electromagnetic Energy traveling in transverse
waves. It can travel through a vacuum where there are no molecules. It includes
different forms of energy but we used it to refer to light energy. It is a form of Kinetic
Energy.
What is sound energy? Sound is produced when a force causes an object or substance to
vibrate — the energy is transferred through the substance in a wave. Typically, the
energy in sound is far less than other forms of energy. Sound Energy is a form of Kinetic
Energy.
What is electrical energy? It is the movement of electrons. Electrical energy is an
example of Kinetic Energy.
What is nuclear energy? The energy stored in the nucleus of an atom that is usually used
for holding protons and neutrons in the nucleus. Nuclear Energy is a form of Potential
Energy. The heat and light from the Sun is a form of nuclear energy.
How are each of these forms of energy related to kinetic and potential energy? See my
answers above
Be able to explain how potential and kinetic energy change (think roller coaster lab and
Energy Skatepark)
Be able to able to identify which forms of energy are being transformed in different situations
Look at your practice sheets
Be able to explain how thermal energy is always a result of an energy conversion Due to friction
Be able to explain why perpetual motion is impossible Due to friction there is not a machine that
is able to go on and on forever without adding more energy to it.
WORK AND POWER
What is work? Work is done when a force transfers energy to an object to make it move a
certain distance in the same direction as the force.
When is work done on an object? When there is a force on an object and the object moves
in the direction of that force.
What is the unit used when measuring work? A Joule (J)
What is a joule (J) equal to? Joule (J) = N•m = kg•m2/s2
What is power? The rate at which work is done or the amount of time it takes to get work
done.
What is a rate? A rate is when an amount of one thing is related to an amount of another
thing. In science we usually use rate to show how doing something is related to the
amount of time it takes to do it.
What is the rate at which work is done? Power
What is the unit used when measuring power? Watt (W)
What is a watt (W) equal to? 1 W = 1 J/s
Look at your 4 readings and your practice sheets:
Be able to recognize examples of when work is and is not being done on an object
Be able to calculate the amount of work done on an object
Be able to calculate the amount of power of an object
Be able to explain the difference between work and power
Be able to apply the ALL vocabulary if given a new situation or scenario
Be able to answer any application questions about any concept we have studied