Ehime Entrance Science flashcards
Ehime Entrance Science · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Newton's second law
- The net force on an object equals its mass times acceleration, F = ma. Acceleration points in the same direction as the net force.
- Conservation of mechanical energy
- Without friction or other nonconservative forces, the sum of kinetic and potential energy stays constant, so ½mv² + mgh is unchanged.
- Ohm's law
- For a resistor at constant temperature, current equals voltage divided by resistance, I = V/R. Doubling voltage doubles current.
- Snell's law
- Light bending at an interface obeys n₁sinθ₁ = n₂sinθ₂, where n is refractive index and angles are measured from the normal.
- Wave equation
- Wave speed equals frequency times wavelength, v = fλ. Frequency is set by the source; speed depends on the medium.
- Latent heat
- Energy absorbed or released during a phase change without temperature change, Q = mL. Melting and boiling use different latent heat values.
- Momentum conservation
- In a system with no external net force, total momentum before and after a collision is equal; in a perfectly inelastic collision the bodies stick together.
- Ideal gas law
- PV = nRT relates pressure, volume, amount, and absolute temperature. Temperature must be in kelvin for the equation to hold.
- Mole calculation
- Amount in moles equals mass divided by molar mass, n = m/M. One mole contains Avogadro's number of particles, about 6.0 × 10²³.
- Limiting reagent
- The reactant consumed first, determined by comparing mole ratios from the balanced equation. It sets the maximum amount of product formed.
- pH scale
- pH = −log[H⁺]. Values below 7 are acidic, 7 is neutral at 25 °C, and above 7 is basic; each unit is a tenfold change.
- Oxidation and reduction
- Oxidation is loss of electrons and an increase in oxidation number; reduction is gain of electrons. Both always occur together in redox reactions.
- Le Chatelier's principle
- When a system at equilibrium is disturbed by concentration, pressure, or temperature change, it shifts to partially oppose the disturbance.
- Ionic versus covalent bonds
- Ionic bonds transfer electrons between metal and nonmetal atoms; covalent bonds share electrons, usually between nonmetals.
- Periodic trends
- Atomic radius decreases left to right across a period and increases down a group. Ionization energy and electronegativity generally show the opposite pattern.
- Functional groups
- Characteristic atom arrangements giving organic molecules their properties: hydroxyl –OH in alcohols, carboxyl –COOH in acids, ester –COO–.
- Molarity
- Concentration expressed as moles of solute per liter of solution, c = n/V. Dilution keeps moles constant: c₁V₁ = c₂V₂.
- Photosynthesis equation
- 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂, driven by light in chloroplasts. Light reactions supply ATP and NADPH for the Calvin cycle.
- Cellular respiration
- Glucose is broken down to release energy: glycolysis in cytoplasm, then Krebs cycle and electron transport in mitochondria, producing ATP and CO₂.
- Central dogma
- Genetic information flows from DNA to mRNA by transcription, then to protein by translation at ribosomes using codon-anticodon pairing.
- Mendel's law of segregation
- Two alleles for a trait separate during gamete formation, so each gamete carries only one allele. Fertilization restores the pair.
- Negative feedback
- A control mechanism in which a deviation from the set point triggers responses that reduce the deviation, stabilizing conditions such as body temperature.
- Natural selection
- Heritable variation plus differential survival and reproduction change allele frequencies over generations, adapting populations to their environment.
- Prokaryote versus eukaryote
- Prokaryotes lack a nucleus and membrane-bound organelles; eukaryotes have a nucleus and organelles such as mitochondria and chloroplasts.
- Energy transfer in ecosystems
- Producers capture light energy; roughly ten percent passes to each higher trophic level, so food chains are short and biomass pyramids narrow.
- Plate boundaries
- Divergent boundaries create ridges, convergent boundaries cause subduction, volcanoes, and mountain building, and transform boundaries produce earthquakes.
- Seismic wave types
- P waves are longitudinal and pass through solids and liquids; S waves are transverse and cannot travel through liquids, revealing a liquid outer core.
- Rock cycle
- Igneous rock forms from cooling magma, sedimentary from deposition and lithification, metamorphic from heat and pressure; processes recycle among all three.
- Earth's magnetic field
- Generated by convection of liquid iron in the outer core through dynamo action; the field has poles that wander and reverse over geological time.
- Seasons
- Caused by the 23.4° tilt of Earth's axis combined with revolution around the Sun, changing sunlight angle and day length, not by distance from the Sun.
- Moon phases
- The changing illuminated fraction seen from Earth over a synodic month of about 29.5 days as the Moon orbits; new moon and full moon occur at opposite positions.
- Atmospheric layers
- Temperature falls with height in the troposphere, rises in the stratosphere where ozone absorbs ultraviolet, then falls again in the mesosphere.