The Astronomical Unit (definition)
The mean distance from the centre of the Earth to the centre of the Sun
1AU = 1.5x10^11m
The Light Year (definition)
The distance travelled by light in one year
1 degree = – arcminutes
60
The Parsec (definition)
A unit of distance that gives a parallax angle of 1 second of an arc using the radius of the Earth’s orbit (1AU) as the baseline of a right-angled triangle
for small angles, tan(p) =
p
Stellar Parallax (definition)
The apparent shifting in a position of a star viewed against a background of distant stars when viewed from different positions of the Earth, such as at different positions of the Earth’s orbit
Stellar parallax can be used to measure (2)
- the distance to nearby stars
- involves observing how the position of a nearby star changes over a period of time against a fixed background of stars
A nearby star will have a — parallax angle
larger
The Doppler Effect (definition)
The apparent shift in wavelength/frequency caused by the relative motion between a wave source and an observer
The Doppler Effect: wavelength if the wave source is moving
- towards an observer
- away from an observer
- shorter
- longer
Red Shift (definition)
The apparent increase in wavelength of em radiation caused when the source is moving away, relative to an observer
The Doppler Effect in stars (4)
- compare the light spectrum produced from the Sun with that of a distant galaxy
- the pattern of lines is shifter towards the red end of the spectrum for stars travelling away from us
- known as red shift
- this is evidence that distant galaxies are moving away from us
Red Shift is more pronounced for (2)
- galaxies that are further away
- Hubble concluded that galaxies which are further away from Earth are moving faster than galaxies which are closer
Hubble’s Law
The recessional velocity of a galaxy is proportional to its distance from Earth
Recessional Velocity (definition)
The velocity of an object moving away from an observer
Estimating the Age of the Universe, use
t = 1/H0
Olber’s Paradox (definition)
An argument in astrophysics that says the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe
Cosmic Background Radiation (definition)
Microwave radiation received from all over the sky originating from the early stages of the universe after the Big Bang
Astronomers found that Microwave Background Radiation has a peak wavelength corresponding to a temperature of
2.7K
Microwave Background Radiation has (2)
- the exact profile expected to be emitted from a hot body that has cooled down over a very long time
- is uniform
Origins of Microwave Background Radiation (4)
- according to the Big Bang Theory, in the early stages of the Universe, matter and antimatter annihilated
- this produced lots of gamma photons (em radiation)
- this radiation has expanded with the expansion of the Universe
- is now in the microwave region of the EM spectrum
The Big Bang Theory (definition) (3)
- the universe was created from a hot singularity which was infinitely dense, hot and small where all of the Universe’s current mass was situated
- there was a giant explosion known as the Big Bang
- time and space were created at this instant
Steady State Theory (definition)
The Universe was static and had always existed and that matter was continually being generated from nothing to account for the expansion of the Universe
General Relativity (definition)
Space and time are connected together a space-time, a property that connects the three dimensions of space and a fourth dimension of time
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GCSE Equations - All34
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Module 1 - 1.1.1 Planning2
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Module 1 - 1.1.2 Implementing1
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Module 1 - 1.1.3 Analysing3
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Module 1 - 1.1.4 Evaluation1
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Module 2 - 2.1.1 Physical Quantities2
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Module 2 - 2.1.2 SI Units9
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Module 2 - 2.2.1 Measurements and Uncertainties9
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Module 2 - 2.3.1 Nature of Quantities2
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Module 3 - 3.1.1 Kinematics7
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Module 3 - 3.1.2 Linear Motion7
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Module 3 - 3.1.3 Projectile Motion1
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Module 3 - 3.2.1 Dynamics6
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Module 3 - 3.2.2 Motion with Non-Uniform Acceleration3
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Module 3 - 3.2.3 Equilibrium10
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Module 3 - 3.2.4 Density and Pressure6
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Module 3 - 3.3.1 Work and Conservation of Energy5
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Module 3 - 3.3.2 Kinetic and Potential Energies1
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Module 3 - 3.3.3 Power1
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Module 3 - 3.4.1 Springs11
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Module 3 - 3.4.2 Mechanical Properties of Matter11
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Module 3 - 3.5.1 Newton's Laws of Motion6
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Module 3 - 3.5.2 Collisions4
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Module 4 - 4.1.1 Charge7
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Module 4 - 4.1.2 Mean Drift Velocity10
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Module 4 - 4.2.2 E.m.f. and P.d.8
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Module 4 - 4.2.3 Resistance6
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Module 4 - 4.2.4 Resistivity6
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Module 4 - 4.2.5 Power3
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Module 4 - 4.3.1 Series and Parallel Circuits2
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Module 4 - 4.3.2 Internal Resistance6
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Module 4 - 4.3.3. Potential Dividers1
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Module 4 - 4.4.1 Wave Motion20
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Module 4 - 4.4.2 Electromagnetic Waves11
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Module 4 - 4.4.3 Superposition9
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Module 4 - 4.4.4 Stationary Waves8
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Module 4 - 4.5.1 Photons3
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Module 4 - 4.5.2 The Photoelectric Effect8
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Module 4 - 4.5.3 Wave-Particle Duality1
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Mock Revision - ignore49
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Astrophysics - ignore37
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Module 5 - 5.1.1 Temperature9
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Module 5 - 5.1.2 Solid, Liquid and Gas14
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Module 5 - 5.1.3 Thermal Properties of Materials3
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Module 5 - 5.1.4 Ideal Gases11
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Module 5 - 5.2.1 Kinematics of Circular Motion3
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Module 5 - 5.2.2 Centripetal Force7
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Module 5 - 5.3.1 Simple Harmonic Oscillations6
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Module 5 - 5.3.2 Energy of a Simple Harmonic Oscillator2
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Module 5 - 5.3.3 Damping14
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Module 5 - 5.4.1 Point and Spherical Masses5
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Module 5 - 5.4.2 Newton's Law of Gravitation1
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Module 5 - 5.4.3 Planetary Motion5
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Module 5 - 5.4.4 Gravitational Potential and Energy9
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Module 5 - 5.5.1 Stars24
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Module 5 - 5.5.2 Electromagnetic Radiation From Stars30
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Module 5 - 5.5.3 Cosmology31
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Module 5 - Detailed Sections of Astrophysics17
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Module 6 - 6.1.1 Capacitors9
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Module 6 - 6.1.2 Energy5
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Module 6 - 6.1.3 Charging and Discharging Capacitors9
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Module 6 - 6.2.1 Point Spherical Charges4
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Module 6 - 6.2.2 Coulomb's Law4
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Module 6 - 6.2.3 Uniform Electric Field2
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Module 6 - 6.2.4 Electrical Potential and Energy8
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Module 6 - 6.3.1 Magnetic Fields16
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Module 6 - 6.3.2 Motion Of Charged Particles8
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Module 6 - 6.3.3 Electromagnetism19
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Module 6 - 6.4.1 The Nuclear Atom12
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Module 6 - 6.4.2 Fundamental Particles14
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Module 6 - 6.4.3 Radioactivity17
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Module 6 - 6.4.4 Nuclear Fission and Fusion15
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Module 6 - 6.5.1 Using X-Rays13
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Module 6 - 6.5.2 Diagnostic Methods in Medicine8
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Module 6 - 6.5.3 Using Ultrasound18
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Module 3 Practicals8
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Module 4 Practicals15
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Module 5 Practicals10
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Module 6 Practicals9
