FAQs Flashcards
How is creativity used in science?
Creativity is used throughout science, across all fields and disciplines and is often what results in new discoveries, procedures, technologies, questions, and of course new knowledge.
How is a systems approach useful in studying Life Science/Biology?
A systems approach is useful in science, especially in Life Science/Biology because it allows scientists to gain a deeper understanding of the system as a whole, and how parts of the system work together; it allows scientists to make predictions, construct models, study interactions, and investigate relationships in a system. The systems approach is useful at all levels of Life Science/Biology -from the microscopic (cell), to the organism, and all the way up to very large scale studies (ecosystems).
What do the units of: Kelvin, Joule, and Newton measure?
Kelvin (degrees K) measures TEMPERATURE, Joule is the SI unit of ENERGY and WORK, Newton (N) is the scientific unit of FORCE.
Do simple machines change the amount of work?
Simple machines do not change the amount of work but rather they affect the amount of input force needed to do the work. Smoke machines decrease the amount of force by increasing the distance over which the force is applied.
What themes unify Biology?
Unifying themes in biology include cells, heritable information, properties of systems, regulation, environmental interaction, energy, unity and diversity, evolution, structure and function, scientific inquiry, and the relationship of science and technology.
What do the fields/areas of study under natural science include and encompass?
Natural Science involves the study of our physical, natural world, therefore it includes Life Science, Chemistry, Earth Science, Physical Science, and Space Science:
Biology: Life Science; the study of life, the study of living things.
Chemistry: the study of molecules, molecular interactions, compounds, and reactions.
Earth Science: involves the fields of Geology, Meteorology, and Oceanography.
Physical Science: the study of forces, energy, motion, and mass.
Astronomy: Space Science; the study of planets, the stars, and the Solar System.
What does the Law of Conservation of Energy state?
Energy cannot be created or destroyed.
What is the inverse square law?
The inverse square law relates to the intensity of an effect being inversely related to the square of the distance from the cause. The inverse square law applies to many things, including gravity and also to light.
Ex: Light from a flashlight - as the light spreads out from the flashlight source, the brightness would decrease.
The law holds for all phenomenon where something from a localized source spreads uniformly throughout the surrounding space.
What is the difference between Coulomb’s Law and Newton’s Law of Universal Gravitation?
Coulomb’s Law describes the relationship among force, charge, and distance. It says if changes are alike, the force is repelling; if the charges are unlike, the force is attractive.
Newton’s Law of Universal Gravitation states that everybody in the universe attracts every other body in the universe with a mutually attracting force, and this will be directly proportional to the product of their masses, and inversely proportional to the square of the distance between them.
What is thermal energy?
Thermal energy involves the total internal energy (kinetic and potential) of particles that make up a substance.
How can objects that have different mass and different volume have the same density?
Since density = mass/volume or D=m/v; Density is measuring how much mass occupies a given space. So objects can have different mass and different volume but can have the same density.
Ex: Water vs. A pond of water - the mass and volume of the two water sources differ, but the density of water is the same.
Why do two objects of different masses fall at the same speed in a vacuum but not outside a vacuum?
In a vacuum the only force acting in the object is weight (due to gravity) whereas in the presence of air, air resistance opposes the gravitational force and therefore decreases the downward force of weight. Lighter objects reach terminal velocity faster and heavier objects have a higher terminal speed.
According to Newton’s 1st Law of Motion, an object at uniform speed will continue moving unless acted on by a nonzero force. What force causes a hockey puck to stop moving on ice?
The friction between the hockey puck and the ice is a nonzero force that eventually brings the puck to a stop.
What is inertia?
Inertia has to do with how much an object resists changing its motion; therefore an object with more mass has more inertia and takes more force to move.
Can light act as both a wave and a particle?
Yes, light has both a wave nature and a particle nature - this is often called a wave-particle duality. In fact, light behaves as a particle when it interacts with matter.
What changes the pitch of a sound?
Sound is caused by air vibrating, and vibration frequency is what changes the pitch of sound.
Ex: High pitch comes from high frequency sound waves with rapid vibrations.
What is the difference between reflection and refraction?
Reflection is the bouncing of a wave (such as light) from a medium of origin, to a barrier, and back to the medium of origin.
Ex: Reflection in a mirror.
Refraction refers to the bending of waves (such as light) due to a change in the medium.
Ex: Looking at an object in a glass of water.
What is an electromagnetic wave?
Wave of energy produced when an electric charge is accelerated; it consists of both an electric field and a magnetic field that are perpendicular to one another.
Which type of electromagnetic radiation contains the most energy?
Gamma rays are the electromagnetic waves with the highest energy. They are used in cancer treatments to kill cancerous cells.
How is ultraviolet radiation different than infrared radiation?
Ultraviolet radiation consists of shorter wavelengths and a higher frequency than infrared. As a result, ultraviolet radiation is higher energy. Ultraviolet radiation can be used for disinfecting water and killing bacteria whereas infrared can be used in remote controls and to determine cloud temperature.
What does Einstein’s equation E=mc2 show?
E=mc2 - Einstein’s famous equation shows that mass and energy are manifestations of the same thing. Known as the mass-energy equivalence, this is an important unifying concept in science.
What is the difference between rad and rem?
A rad is a unit of “radiation absorbed dose” (rad) - so it refers to the absorbed dose of radiation; it is related to amount of energy absorbed/deposited in say a metal pipe, or a nuclear plant, these would be reported in rads.
And rem is a unit that measures biological risk to exposure to radiation - so rem refers to the risk to biological tissues from radiation exposure, it stands for “Roentgen Equivalent Man” (rem); so when you go to the dentist or doctor or even fly on a plane your radiation exposure to X-rays and cosmic rays are reported in rem.
What are the components of an atom?
An atom is composed of subatomic particles; electrons, protons, and neutrons.
The protons and neutrons are located within the atom’s nucleus, while the electrons are found surrounding the outside of the nucleus.
How does the mass per nucleon change in a fusion reaction?
Although the resulting helium - 4 nucleus has more nucleons than two hydrogen - 2 nuclei from which it formed, the mass of each nucleon in less in the helium - 4 nucleus than in the hydrogen - 2 nuclei. The lost mass is converted to energy during the fusion reaction.
How does the mass of each nucleon in a uranium-235 nucleus differ from the mass of each nucleon in its fragments?
During fission mass is converted to energy resulting in less mass per nucleon in the uranium fragments compared with the original uranium-235 nucleus.
What is the difference between fission and fusion?
Nuclear fission is the splitting of nuclei. Nuclear fission often produces highly radioactive particles and an example of fission is the atom bomb.
Nuclear fusion is the combining of nuclei. An example of fusion occurs in stars, such as the Sun.
In BOTH fission and fusion, MASS is converted to kinetic ENERGY.
What is the general chemical composition of stars?
Stars are composed of mostly Hydrogen (H), some Helium (He), and very small traces of heavier chemical elements.
What is a black hole?
A black hole is the remains of a giant star that underwent gravitational collapse to itself; this collapse results in mass so compressed that it causes an infinite space-time curvature, where light itself cannot even escape! Einstein’s General Theory of Relativity provides a foundation for understanding black holes.
Why do massive stars have shorter lives?
Massive stars must be more luminous in order to offset the gravitational force of contraction. To be more luminous they burn hydrogen fuel at a faster rate than small-mass stars resulting in shorter lives.
What is the Hertzsprung-Russell (H-R) diagram?
It is a diagram that plots the luminosity and surface temperature of stars. There are distinct regions on the diagram including main sequence, red giants, and white dwarfs.
After our Sun burns up its supply of hydrogen, what kind of star will it most likely become?
It will become a Red Giant. Like all stars, our Sun follows a life cycle, and it is currently classified as a yellow dwarf star about 5 billion years old. Upon its death, it will be a cold, black dwarf.
How does the Sun influence the organization of the Solar System?
The Sun is the center of our Solar (Sun) System, and also happens to be the closest stars the Earth. Objects in the Solar System are gravitationally bound to the Sun, therefore it is the Sun’s gravity that organizes the shape of our Solar System, the elliptical orbits of the planets, and also influences the system’s evolution. In fact, the Sun itself contains most of the mass of the Solar System.
Which planet in our solar system most closely resembles Earth?
Venus. It is a similar distance from the Sun and is close to the same size and density.
Where does thermonuclear fusion occur in the Sun?
Thermonuclear fusion occurs in the core of the Sun and then is radiated outward towards the surface.
What are the Jovian planets?
The Jovian planets are gaseous planets including Saturn, Uranus, Jupiter, and Neptune.
The Jovian planets are found further out from the Sun, and are gaseous in nature.
This is in contrast to the terrestrial planets which are found closer to the Sun (like Earth) and are rocky in nature, since they were formed from materials with very high melting points.
What is the Big Bang and what evidence exists of its occurrence?
The universe began in a primordial explosion, known as the Big Bang, around 13.7 billion years ago and has been expanding ever since. Seem evidence for Big Bang includes the slowing of the galaxies as they recede/expand, and also the long wavelength radiation that permeates the universes.
What is a pulsar?
A pulsar is a core of neutrons (neutron star) that remain after a supernova and emit rapidly varying sources of low-frequency radio waves.
What kinds of tools are used to observe objects in the Universe?
Because several different types of electromagnetic radiation exist in the Universe, tools have been developed to detect these types of radiation. There are optical telescopes, infrared telescopes, gamma ray telescopes, radio telescopes, optical spectrographs, ect. Astronomers use different tools to study different aspects of the Universe.
What is cosmic background radiation?
Cosmic background radiation is faint microwave radiation detected it the Universe and is thought to be emitted as a result of the Universe cooling off following the Big Bang explosion.
