Final Science Review Flashcards

A comprehensive set of flashcards covering hypotheses, experimental design, graphing, Newton’s laws, forces, energy, Earth science, plate tectonics, earthquakes, and climate concepts from the lecture notes.

What is a scientific hypothesis?

An educated, testable prediction often written in the form: If [independent variable], then [dependent variable], because [scientific reason].

Give the format for writing a hypothesis.

If [I do this], then [this will happen], because [scientific reason].

Which variable is deliberately changed in an experiment?

The independent variable.

Which variable is measured as a response in an experiment?

The dependent variable.

What are controlled variables?

Factors kept the same to ensure a fair test.

In a plant-sunlight experiment, name the independent variable.

Amount of sunlight.

In the same plant-sunlight experiment, name the dependent variable.

Plant height (growth).

What purpose does a control group serve?

Provides a baseline for comparison by not receiving the independent variable.

List two reasons for repeating experiments.

To detect errors and to increase reliability/obtain better averages.

Define reliability in scientific experiments.

The degree to which results are consistent and trustworthy.

What are the main parts of a scientific procedure?

Materials list, numbered steps, clear verbs, safety notes, number of trials.

Name four clear action verbs often used in procedures.

Measure, pour, record, repeat.

On a speed–distance graph, what does a straight upward line indicate?

Constant speed.

On a speed–distance graph, what does a horizontal line indicate?

The object is stopped (zero speed).

What does a steeper line mean on a speed–distance graph?

Faster speed.

On a velocity–displacement graph, what does a positive slope show?

Motion in the forward direction.

On a velocity–displacement graph, what does a curved line signify?

Changing velocity (acceleration or deceleration).

Differentiate qualitative and quantitative data.

Qualitative = descriptive (color, texture); Quantitative = numerical (mass, temperature).

Which axis is used for the independent variable on a graph?

X-axis.

Which axis is used for the dependent variable on a graph?

Y-axis.

State Newton’s First Law of Motion.

An object at rest stays at rest and an object in motion stays in motion at constant velocity unless acted on by an external unbalanced force.

What is inertia?

An object’s tendency to resist changes in its motion; greater mass means greater inertia.

Why does a rolling ball eventually stop on Earth?

Unbalanced forces such as friction and air resistance slow it down.

State Newton’s Second Law of Motion.

Force equals mass times acceleration (F = ma).

What kind of force results in acceleration?

An unbalanced force.

Give two examples of unbalanced forces causing negative acceleration.

Gravity slowing a ball thrown upward; brakes slowing a car.

State Newton’s Third Law of Motion.

For every action, there is an equal and opposite reaction.

When you walk, which force pair illustrates Newton’s Third Law?

Foot pushes backward on ground (action); ground pushes foot forward (reaction).

Write the speed formula.

Speed = Distance ÷ Time.

What are typical SI units for speed?

Metres per second (m/s) or kilometres per hour (km/h).

Convert 1500 mL to litres.

1.5 L.

How many cm³ are in 1 mL?

1 cm³ = 1 mL.

Define gravitational potential energy and give an example.

Energy stored due to height above Earth’s surface; e.g., a book on a shelf.

List three other forms of energy besides gravitational, thermal, and chemical.

Kinetic, sound, light (also nuclear, elastic).

Describe the energy transformation in a toaster.

Electrical energy → Thermal energy.

What is Earth’s average gravitational acceleration?

9.8 m/s² downward.

Name the four Earth spheres.

Lithosphere, hydrosphere, atmosphere, biosphere.

Which Earth sphere includes all water?

Hydrosphere.

Who proposed continental drift?

Alfred Wegener.

State two pieces of evidence Wegener used for continental drift.

Matching fossils on different continents; continents fit like puzzle pieces.

Who provided sea-floor spreading evidence supporting plate tectonics?

Harry Hess.

What process occurs at mid-ocean ridges?

Divergent plates spread apart and new oceanic crust forms (ridge push).

Explain slab pull.

The sinking of a denser oceanic plate at a trench pulls the rest of the plate with it.

Name the three main compositional layers of Earth.

Crust, mantle, core.

Which layer generates Earth’s magnetic field?

The liquid outer core.

List the five mechanical (physical) layers of Earth.

Lithosphere, asthenosphere, mesosphere, outer core, inner core.

Describe the asthenosphere.

Semi-solid, plastic layer in upper mantle on which tectonic plates float.

What rock type composes most oceanic crust?

Basalt (dense, dark volcanic rock).

Which crust is thicker, continental or oceanic?

Continental crust.

Name the three types of plate boundaries.

Convergent, divergent, transform.

What landform is commonly created at oceanic-continental convergent boundaries?

Volcanic mountain arcs or volcano chains near trenches.

Give an example of a transform boundary.

San Andreas Fault, California.

Why are divergent boundaries called “constructive”?

Because new crust is created as plates move apart.

What is the fastest seismic wave?

Primary (P) wave.

Which seismic wave travels only through solids?

Secondary (S) wave.

Which waves cause the most earthquake damage?

Surface waves (Love and Rayleigh).

Define base isolation in earthquake engineering.

Placing flexible pads between a building and its foundation to absorb seismic motion.

What is the purpose of dampers in buildings?

Act as shock absorbers, dissipating energy to reduce vibration during earthquakes.

Where do most land volcanoes form?

Near convergent plate boundaries at subduction zones adjacent to trenches.

What is a volcanic hotspot?

A mantle plume where magma breaks through a plate away from boundaries, e.g., Hawaii.

Name the process that forms fold mountains.

Collision of two continental plates at convergent boundaries.

How do fault-block mountains form?

Crust is stretched at divergent boundaries; blocks rise or sink along faults.

What evidence for sea-floor spreading comes from magnetic stripes?

Symmetrical patterns of magnetic reversals recorded in oceanic crust on both sides of ridges.

Explain convection currents in the mantle.

Hot rock rises, cools near the crust, sinks, creating a cycle that moves plates.

What is ridge push?

Newly formed, cooling crust at a mid-ocean ridge becomes denser and slides away, pushing plates.

Describe the greenhouse effect.

Atmospheric gases trap some outgoing heat, keeping Earth warm enough for life.

List three major greenhouse gases enhanced by human activities.

Carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O).

Give two effects of global warming.

Melting glaciers/rising sea levels; more extreme weather (droughts, floods).

What is the typical density difference between basalt and granite?

Basalt (oceanic crust) is denser; granite (continental crust) is less dense.

Define a transform fault.

A boundary where two plates slide horizontally past each other.

What is a seismic fault line’s key characteristic?

Numerous, discontinuous cracks often running roughly parallel in zones.

How can earthquakes impact the hydrosphere?

Trigger tsunamis, alter water flow, cause floods, damage dams.

Which two innovative designs help buildings resist earthquakes?

Base isolation and dampers.

Why is the outer core liquid while the inner core is solid?

Lower pressure in outer core allows iron-nickel to stay liquid; immense pressure solidifies inner core despite higher temperature.

What is slab pull responsible for at a subduction zone?

Dragging the rest of the plate downward, aiding plate motion.

Give the equation that relates velocity, displacement, and time.

Velocity (v) = Displacement ÷ Time.

Define acceleration in simple terms.

Any change in velocity (speeding up, slowing down, or changing direction).

What unbalanced force slows a ball rolling on grass?

Friction between the ball and ground (plus air resistance).

How does a car maintain constant velocity on a flat road despite friction?

The engine provides a forward force that balances resistive forces.

Name two main forces acting on a book resting on a table and their balance status.

Gravity (down) and normal force from table (up); they are balanced, so the book stays still.