Nature of Science Overview

Nature of Science

• Scientific Method: A series of steps used to investigate natural occurrences or solve problems.
• Question/Problem: A question or problem that can be solved through experimentation.
• Hypothesis: A proposed answer to a problem or question, often stated as a prediction.
• Independent Variable: The variable that is intentionally changed by the experimenter.
• Dependent Variable: The variable that might change as a result of changes to the independent variable.
• Experiment: A procedure that includes a detailed materials list, measurable (quantifiable) outcomes, and allows for repetition.
• Control Group: A standard of comparison in an experiment.
• Constants: Factors the experimenter attempts to maintain the same across all experimental groups.
• Scientific Law: A statement about natural occurrences.
• Scientific Theory: An explanation of observations supported by evidence.
• Mass: The amount of matter in an object.
• Volume: The amount of space an object occupies.
• Length: The distance between two points.
• Meter: The base unit of length in the metric system.
• Gram: The base unit of mass in the metric system.
• Liter: The base unit of volume in the metric system.

Metric Conversions & Measurements

• Learn to convert between metric units.
• Master the procedure of finding volume using water displacement.
• Understand the order of metric unit prefixes.

Speed, Velocity, and Acceleration

• Speed: How fast an object is moving.
• Motion: The act of moving.
• Velocity: Speed and direction of an object's motion.
• Acceleration: The rate of change in velocity.
• Reference Frame: The background used to define an object's motion.
• Positive Acceleration: A positive number on a velocity-time graph with a positive slope.
• Negative Acceleration: A negative number on a velocity-time graph with a negative slope (deceleration).
• Speed Formula: Speed = Distance / Time
• Velocity Formula: Velocity = Distance/Time with direction.
• Acceleration Formula: Acceleration = (Final Velocity - Initial Velocity) / Time
• Calculate speed, velocity, and acceleration from word problems, graphs, and charts.
• Convert minutes to seconds.
• Interpret speed and acceleration graphs.
• Round to the nearest hundredth.
• Properly use units in calculations.

Force and Newton's Laws

• Force: A push or pull exerted on an object.
• Gravity: A force that pulls objects downwards.
• Free Fall: Motion where only gravity acts on an object.
• Isaac Newton: Described the relationship between motion and force.
• Friction: A force opposing motion between two touching surfaces.
• Rolling Friction: Friction between a rolling surface and another surface.
• Sliding Friction: Friction between two sliding surfaces.
• Static Friction: Friction between two surfaces that aren't moving.
• Weight: The force of gravity on an object.
• Balanced Force: Forces that don't change an object's motion (net force is zero).
• Unbalanced Force: Forces that do change an object's motion (net force is not zero).
• Net Force: The combination of all forces acting on an object.
• Inertia: The tendency of an object to resist changes in its motion.
• Air Resistance: Friction between a moving object and air molecules.
• Newton's First Law: An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
• Newton's Second Law: Force = mass × acceleration.
• Newton's Third Law: For every action, there is an equal and opposite reaction.
• Calculate force, net force, and weight.

Work, Power, and Machines

• Work: The transfer of energy when a force moves an object over a distance.
• Power: The rate at which work is done.
• Machine: A device that makes work easier.
• Mechanical Advantage: The advantage gained by using a machine (output force/input force).
• Input Force: The force applied to a machine.
• Output Force: The force exerted by the machine.
• Simple Machines: Machines that do work in one movement.
• Complex Machines: Machines that consist of multiple simple machines working together.
• Work Formula: Work = Force × Distance
• Power Formula: Power = Work / Time
• Mechanical Advantage Formula: Mechanical Advantage = Output Force / Input Force.
• Understand how different simple machines (levers, pulleys, inclined planes, screws, wedges, and wheel & axles) work and the mechanical advantage of each.

Energy

• Law of Conservation of Energy: Energy cannot be created or destroyed; it can only change form.
• Types of Energy: Chemical, nuclear, electrical, magnetic, light, sound, electromagnetic, mechanical, heat.
• Energy Transformations: Examples of energy changing from one form to another.

Electricity

• Electricity: The flow of electrons.
• Law of Charges: Opposites attract, likes repel.
• Static Electricity: Accumulation of electric charges producing a discharge. (Conduction, Induction, Friction)
• Current Electricity: Flow of electrons through a circuit (needs a closed circuit).
• Ohm's Law: (Relates current, voltage, and resistance).
• Parallel Circuits: Current alternates.
• Series Circuits: Current flows in one direction.

Magnetism

• Magnetism: A force and type of energy.
• Magnet Strength: Strongest at its magnetic field.
• Magnetic Poles: Two opposite poles; where magnetism is strongest.
• Electromagnet: Electricity creates a magnetic field. (Ways to strengthen an electromagnet, coil number, wire thickness, metal size, battery size)
• Magnetization: Organized electron alignment.

Waves

• Wave Properties: Definition, medium, direction of energy transfer and particles, frequency, wavelength, amplitude, compressional vs. transverse waves.
• Types of Waves: Mechanical, electromagnetic
• Transverse Waves: Matter moves up and down perpendicular to wave motion (Examples: crowd wave).
• Compressional (Longitudinal) Waves: Matter moves back and forth in the same direction as the wave motion. (Examples: Slinky).
• Wave Components: Crests, troughs, amplitude, wavelength, frequency.
• Electromagnetic Spectrum: Characteristics
• Wave Phenomena: Reflection, refraction, diffraction, interference, constructive and destructive interference

Sound

• Sound: A compressional wave produced by vibrating matter.
• Sound Transmission: Needs a medium to travel (air).
• Sound Speed: Different speeds in different media.
• Sound Pitch: Depends on frequency.
• Doppler Effect: Observed change in frequency when source or observer is moving.

Light

• Light: Allows us to see.
• Light Interaction with Objects: Reflection, refraction, transmission.
• Law of Reflection: Incidence angle = Reflection angle.
• Visible Spectrum: The combination of colors of visible light.
• Color Perception: An object absorbs colors not reflected.

Heat and Temperature

• Heat and Matter: The universe is matter and energy, matter is made of atoms, and atoms are always in motion.
• Temperature: Average kinetic energy of particles.
• Temperature Measurement: Thermometers, qualitative vs. quantitative data.
• Heat Transfer: Conduction, convection, radiation.
• Specific Heat: Amount of heat needed to raise 1 kg of a material by 1°C. (Units, formula, meaning of variables, and calculations)