Physics Final Review (Semester 2) Flashcards
A light-year equals what distance
9.46 trillion km, 5.88 trillion miles
Which event began the universe
The Big Bang
A constellation’s changing position in the sky, at the same time of the evening, over a period of several weeks is evidence that
Earth revolves around the Sun
The telescope that solved the problem of color separation was the
reflecting telescope
The Coriolis effect provides evidence that
the Earth rotates
The Coriolis effect is
because the Earth rotates on its axis, circulating air is deflected toward the right in the Northern hemisphere and to the left in the southern hemisphere.
Which telescope detects invisible electromagnetic radiation
A radio telescope
The period between successive full moons is
lunar month
Each of Earth’s standard time zones covers about how many degrees
15
A benefit that 20th and 21st century space programs have brought to an area outside of astronomy is
improved heart pumps and accurate weather predictions
The right combination of temperature, water, and oxygen
supports life on Earth (Goldilocks Zone)
Kepler’s first law states that planets orbit the sun in paths called
ellipses
Young Earth formed a core, mantle, and crust in a process called
differentiation
Early fresh water oceans became salty when
rainwater carried dissolved solid rock to the oceans
The two inner planets most alike in size, mass, and density are
Venus and Earth
Kepler’s third law describes the relationship between the average distance of a planet from the sun and the planet’s
orbital period
Which planet has volcanic regions that may still be active
Mars
Kepler’s second law states that equal areas are covered in equal amount of time as an object
completes an eclipse
What planet has to most complex ring system
Saturn
The early atmosphere developed when many volcanic eruptions released large amounts of gases in a process called
outgassing
Tides on Earth are caused by
Earth’s inertial force and the moon’s gravitational force
When a meteoroid hits Earth, it is called a
meteorite
The idea that the moon’s development began when a large object collided with Earth is called the
giant-impact theory
The moon today looks as it did 3 billion years ago because
it doesn’t have volcanoes
What is not a characteristic of one of the Galilean moons
Ganymede has lava plains
Kuiper Belt
Mainly icy bodies beyond the orbit of Neptune
Oort Cloud
distant spherical region of icy comet nuclei, farthest from the sun, and is the source of most long-period comets
How long is the average sunspot cycle
11 years
What is the hottest layer of the sun’s atmosphere called
corona
Energy is the result of
nuclear fusion
The temperature of the sun’s core is appoximately
15,000,000
What elements make up most of the sun’s mass
hydrogen (92.1%) and helium (7.9%)
Which of the following are part of the sun’s atmosphere
photosphere and chromosphere
Particles thrown off the sun’s corona that can affect Earth’s magnetic field are called
a coronal mass ejection
Einstein’s equation E=mc^2 helps scientists understand the sun’s energy because the equation
explains how mass can be converted into huge amounts of energy
The most common element in most stars is
hydrogen
Stars appear to move in circular paths through the sky because
Earth rotates on its axis
A nebula begins the process of becoming a protostar when the nebula
Begins to shrink and increases its spin
The brightest star in the night sky is
Sirius
A main sequence star generates energy by fusing
hydrogen and helium
The heaviest element formed in the core of a star is
Iron
The change in position of a nearby star as seen from different points on Earth’s orbit compared with the position of a faraway star is called
parallax
Describe what scientists think will happen to the sun in the next 5 billion years
It will expand into a giant red star (engulf Mercury + Venus + Earth) and turn into a white dwarf
If the spectrum of a star indicates that the star shines with red light, what is the approximate surface temperature of the star
2500K - 3500K
Explain why an old main -sequence star is made of a higher percentage of helium than a young main sequence star is
older stars have fused and converted greater amounts of hydrogen into helium
What is the unit for work and energy
Joules
Unit for Power
Watts
Six simple machines
lever, wheel and axle, inclined plane, pulley, screw, wedge
Input force
The force that you exert on an object
Output force
the force the machine exerts on an object
Input distance
the input force moving a machine a certain distance
output distance
the output force exerted over a distance
Kinetic energy
the energy an object has because of its motion
potential energy
stored energy in an object
thermal energy
energy contained within a system that’s responsible for its temperature- the addition of kinetic and potential energy
Elastic potential energy
energy stored in stretched/compressed objects
Gravitational potential energy
due to an object’s position in the gravitational field
Entropy
degree of disorder or uncertainty
Transverse wave
a wave that disturbs the particles in the medium PERPENDICULAR to the direction of the wave’s travel
Example of transverse wave
guitar string or water ripples
Longitudinal wave
The disturbance is PARALLEL to the direction of the wave’s travel
Example of longitudinal wave
Sound waves
What is wavelength measured in
meters
The speed of a sound wave depends on
the medium
The loudness of a sound wave depends on
amplitude
The pitch of a sound wave depends on
frequency
What causes sound waves
Object vibrations and produce pressure waves
What is the Doppler effect
An increase or decrease in the frequency of sound, light, or other waves as the source or observer move towards or away from one another
amplitude
the middle measurement of the amount of energy transferred by a wave
Crest
Maximum point where displacement of medium is at max
Decibel
A logarithmic unit used to measure sound level
Doppler Effect
Effect produced by a moving source on waves
Energy
THe ability of an object to produce a change in itself or its surroundings
Frequency
The number of waves that pass a given point in one second
Hertz
Unit of frequency
Gravitational Potential Energy
The potential energy of a massive object has due to its position in gravitational field
Inclined plane
simple machine consisting of a sloping surface
Joule
SI unit for energy or work
Kinetic Energy
energy an object produces due to motion
Lever
simple machines made of rigid beam and a fulcrum
Period
Time required for one complete cycle of a vibration to pass a given point
Pitch
Measure of sound frequency expressed in Hertz
power
Amount of energy transferred per unit of time
Screw
Simple machine that converts rotational motion to linear motion
Pulley
Simple machines used to change the direction or magnitude of a force
Simple machine
makes work easier for us by allowing to use less effort
Transverse Wave
A wave that disturbs the particles in the medium PERPENDICULAR
Watt
Measure of the rate of energy transfer over a unit of time
Wave
Disturbance or variation that transfers energy from point to point in a medium
Wavelength
Distance between successive crest of a wave
Wedge
Simple machines that has a triangular shape
Wheel and Axle
SImple machine that two circle rotate together around same axis
Work
energy transferred to or from an object
According to EInstein’s theory of relativity, what does a massive body do to the space around it
causes it to curve
How do air bags reduce injuries
they increase the time, thereby reducing force
Power can be described as
the rate of work done
In which unit is work measured
Joules
Which of the following simple machines is found in a pair of scissors
lever
A measure of disorder in a system is called
entropy
A detected change in the frequency of a sound due to a moving source or a moving observer is
the Doppler effect
Loudness of sound depends on the
amplitude
Pitch of sound depends on
frequency
Frequency is measured in
Hz, Hertz
Sound is produced when there are
oscillations in air pressure
A description of a rule of nature is a
Scientific law
Which prefix denotes the smallest amount
Nano
hypothesis can best be defined as a
prediction
The amount of time it takes to complete one complete cycle is the
period
A _____ is a material with zero resistance
superconductor
In a _____ there is only ONE path for the current to flow
series connection
In a ____ there are multiple paths for the current to flow
parallel connection
How as the narrator of the Cosmos episode entitled “Electric Boy”
Neil deGrasse Tyson
Who is the “Electric Boy”
Michael Faraday
Current is measured in units called
amperes
What is loudness measured in
dB, Decibels
