Physics Flashcards
Physics
What are the four fundamental forces?
- Gravity
- The weak force
- Electromagnetism
- The strong force
Physics
True/False.
Even though the strong force is the strongest of all the fundamental forces, it is electromagnetic force that dominates at the scale of cosmology.
False.
Even though the strong force is the strongest of all the fundamental forces, it is gravitational force that dominates at the scale of cosmology.
Physics
For what is the weak force responsible?
Particle decay
(via exchange of bosons)
Physics
What is responsible for the normal force that opposes gravity (for example: in keeping a book on a table instead of letting the book fall through the table)?
(Another way of thinking about it: what interaction allows us to interact with anything at all?)
Electromagnetic interactions
(e.g. electrons in the book opposing electrons in the table)
Physics
Which is far and away the strongest of the four fundamental forces?
The strong force
Physics
For what is the strong force responsible?
Binding subatomic particles together (e.g. quarks) and also atomic particles together (e.g. neutrons and protons)
Physics
True/False.
Electric and magnetic forces are separate and distinct from one another.
False.
They are manifestations of the same electromagnetic force.
Physics
The equation E = mc2 shows the relationship between what two factors?
A nucleus’ mass defect and its binding energy
Physics
What is Newton’s first law of motion?
An object in motion will continue with constant velocity unless acted upon by a net force.
Physics
What is Newton’s second law of motion?
F = ma
Physics
What is Newton’s third law of motion?
For every force exerted by one object on a second, an equal and opposite force is exerted by the second back on the first.
Physics
What is the zeroth law of thermodynamics?
If two thermodynamic systems are both in thermal equilibrium with a third system, then they are in thermal equilibrium with each other.
(I.e., there is a transitive relationship between the systems.)
Physics
What is the first law of thermodynamics?
Conservation of energy
Physics
What is the second law of thermodynamics?
Entropy increases
(randomness increases)
(the tendency of natural processes to lead towards spatial homogeneity of matter and energy)
Physics
What is the third law of thermodynamics?
For a system at absolute zero, entropy is zero
Individuals who use the first or second laws of thermodynamics as tools for undermining well-accepted cosmological and evolutionary theories are often doing so via what mistaken understanding of the laws of thermodynamics?
Often, the arguments ignore the fact that the first and second laws only apply in closed systems.
Physics
What equations can be used to map out the relationship between electric and magnetic fields?
Maxwell’s equations
Physics
What is the use of the Schrodinger equation?
Modelling matter as a wave
(rather than a particle)
Physics
What formula is used to calculate kinetic energy?
KE = ½mv2
Physics
What formula is used to calculate gravitational potential energy?
PE = mgh
Physics
How can electric and magnetic waves be modelled in the same graph?
The electromagnetic wave represents an oscillation in the electric field in one direction and an oscillation in the magnetic field in the perpendicular direction
Physics
True/False.
Sound waves are transverse.
False.
Sound waves are longitudinal.
Physics
True/False.
Light waves are transverse.
True.
Physics
What is the relationship between wave speed, wavelength and frequency?
vc = f λ
Physics
What is Ohm’s law?
V = IR
Physics
What is the name of the phenomenon whereby sounds appear higher-pitched when the emitting source is moving closer to the observer and lower-pitched when moving away?
The Doppler effect
Physics
What is Snell’s law of refraction (light moving from a substance of one density to another)?
Physics
Give a basic explanation for how electricity works.
Electrons flow down a voltage difference
Physics
What is the speed of light?
3 * 108 m/s
Physics
What is the speed of sound?
340 m/s
Physics
Decibels are measured along a __________ scale.
Decibels are measured along a logarithmic scale.
Physics
The visible light spectrum spans what electromagnetic wavelengths?
~400 nm (violet) to ~750 nm (red)
Physics
Arrange these electromagnetic waves by order of ascending wavelength (starting with visible light):
Microwaves
Infrared waves
Radio waves
Visible light
Infrared waves
Microwaves
Radio waves
Physics
Arrange these electromagnetic waves by order of descending wavelength (starting with visible light):
X-rays
UV rays
Gamma rays
Visible light
UV rays
X-rays
Gamma rays
Physics
What mnemonic can be used to remember the overarching difference between general relativity and special relativity?
- General relativity relates to Gravity
- Special relativity relates to Speed
Physics
What is a simplified explanation of general relativity?
All the universe is made of 4-dimensional space-time that can be stretched/curved by mass, thus giving rise to gravitational forces (as a form of accelerative inertia as masses ‘roll’ into the curved depressions created by other masses).
Physics
How does general relativity explain black holes?
When an object is sufficiently massive, it will create a large enough ‘well’ in space-time that not even light can escape.
Physics
What is a simplified explanation of special relativity?
(Note: there are two main postulates that lead to the conclusions.)
- The speed of light is constant in all reference frames
- The laws of physics are identical in all inertial reference frames
Thus, at very high speeds, time dilates and space contracts.
Physics
Explain the special relativity lightbulb-train analogy.
Physics
One twin gets on a spaceship and travels at near the speed of light for a period of time. The other twin stays on earth. Which twin will appear to have aged more when the spaceship lands?
The twin who stayed on earth. (Time has dilated for the twin travelling as very high speeds.)
Physics
Name the main forms of inter-atomic and/or molecular bonding according to the following descriptions:
Complete transfer of an electron (strongest)
Sharing of electrons (strong)
Electromagnetic actions typically via hydrogen-oxygen bonds (weak)
Electromagnetic interactions via dipoles (weaker)
Electromagnetic interactions via transitory dipoles (weakest)
Ionic (strongest)
Covalent (strong)
Hydrogen-bonding (can also be sulfur, nitrogen, etc. instead of oxygen) (weak)
Dipole-Dipole (weaker)
London dispersion (aka van der Waals) (weakest)
Physics
What equation connects pressure, area, and force?
Pressure = Force / Area
Physics
In simple terms, what is gravity?
Curved space-time
Physics
What does it mean that space is a vacuum and not a void?
It is full of energy
(and sometimes particles spring into existence out of the energy)
Physics
At a fundamental level, electrons, quarks, neutrinos, etc. are just what?
Vibrating energy fields
Physics
At the most fundamental level, everything is made up of what subatomic particles?
Quarks (two kinds)
Gluons
Photons
Electrons
Physics
The strong force really refers to the interactions between _______s and _______s.
The strong force really refers to the interactions between quarks and gluons.
Physics
What are gluons?
The particles that bind quarks together
(forming protons and neutrons)
Physics
What particle is responsible for binding electrons to nuclei (similar to how gluons bind quarks together)?
Photons
Physics
What are quarks, gluons, photons, and electrons?
These particles are energy fields where mass, charge, and spin are concentrated
Physics
The subatomic particles (quarks, gluons, electrons, photons) have a wave-particle duality and are really just energy fields where _______, _______, and _______ are concentrated.
The subatomic particles (quarks, gluons, electrons, photons) have a wave-particle duality and are really just energy fields where mass, charge, and spin are concentrated.
Physics
What does it mean that photons (and thus, light) have a wave-particle duality?
Light is both photon packets and also electromagnetic waves
Physics
How can we tell that space is not technically a void?
It has mass and density
Physics
Describe the three major forms of energy transfer.
Conduction, radiation, convection
Physics
Describe the gist of quantum physics.
The physics of atomic and subatomic particles that deals with energies (rather than forces) and the wave-particle duality of very small quantities.
Physics
Describe the gist of quantum physics in terms of uncertainty and entanglement.
- The uncertainty principle — the wave-particle duality makes predicting the actual location and spin of a physical quantity prior to measurement.
- Quantum entanglement — across any distance, some particles seem to be connected in terms of spin, position, momentum, and polarization
Physics
Describe the visual format of the hydrogen wave functions.
Physics
Describe the sp3 orbital hybridization of the valence electrons in a carbon atom.
Physics
Describe the electron fields of the s (x1), p (x3), d (x5), and f (x7) orbitals.
Physics
What is the equation for the resistance a fluid meets while traveling through a tube?
R = 8 * viscosity * length / ∏ * radius4
What is the ideal gas law?
PV = nRT
Physics
What is Boyle’s gas law?
Pressure1 * Volume<u>1</u> = Pressure2 * Volume<u>2</u>
Physics
What is Charles’ gas law?
Volume<u>1</u> / Temperature1 = Volume<u>2</u> / Temperature2
Physics
How does the water pressure at the bottom of a set of open tanks vary between tanks if the tanks are of equal heights but different shapes; e.g., square, rectangular, conical (with the narrow end at either the bottom or the top), round, irregular, etc.?
It doesn’t change at all; the pressure is only dependent on the height of the water.
How is velocity different from speed?
Speed = distance displaced / time
Velocity = distance displaced in a certain direction / time
Physics
How are speed, velocity, and acceleration different from one another?
Speed = distance displaced / time
Velocity = distance displaced in a certain direction / time
Acceleration = change in velocity / time
Physics
What is the value for the acceleration caused by gravity at the earth’s surface?
9.8 m/s2
Physics
What is the basic equation for momentum?
Momentum (p) = mass * velocity
Physics
What is the basic equation for power?
Power = joules / time
(Note: joules can be used in terms of work; i.e., ΔKE)
Physics
What equation relates voltage, power, and current?
Power = current * voltage
P = IV
Physics
How is the resistance calculated for a circuit in series?
RTotal = R1 + R2 + R3 + …
Physics
How is the resistance calculated for a circuit in parallel?
1/RTotal = 1/R1 + 1/R2 + 1/R3 + …
Physics
Where are the alkali earth metals, alkaline earth metals, transition metals, and other metals on the periodic table of elements?
Physics
Where are the metalloids, nonmetals, halogens, and noble gases on the periodic table of elements?
Physics
Where are the lanthanoids and actinoids on the periodic table of elements?
Physics
What is the force that drives small particles (< 0.3 microns) into N95 filters?
What is the force that drives large particles (> 0.3 microns) into N95 filters?
Brownian motion
Inertia
Physics
These equations are known as what?
The kinematic equations
Physics
How are velocity components broken down?
