Topic 1
Motion, forces, and energy — from vectors and kinematics to momentum, energy, and pressure.
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The circular movement of the Earth about its own axis.
Defined by v = 2(pi)r / T, where r is average orbital radius and T is the orbital period.
Eight planets and their moons orbiting the Sun, plus smaller bodies such as comets, asteroids, and meteoroids.
The average distance from the orbiting body to the object it orbits.
Time taken by one object to complete a full orbit around another.
The gravitational force exerted per unit mass at a point; symbol g.
Clouds of dust, plasma, and gases found throughout galaxies, including ours.
A rotating structure of gas, plasma, and dust surrounding objects like stars or black holes.
Information about the planets obtained from research and exploration.
Massive, self-luminous celestial objects composed mainly of hydrogen and helium.
Young stars formed by accretion within a nebula.
Stars in hydrostatic equilibrium: outward gas pressure balances inward gravitational pull (e.g. the Sun).
A bright, luminous, stable star located in a spiral arm of the Milky Way and at the centre of the Solar System.
A vast system of billions of stars with their systems, gas, and dust bound by gravity; over a hundred billion exist in the universe.
Our spiral galaxy containing the Solar System and billions of stars.
All of space, time, matter, and the laws that govern them.
The distance light travels in a vacuum in one year.
Luminous, cool-surface stars in late evolution with large radii and reddish-orange colour (e.g. Aldebaran, Mira).
Red supergiants are aging giant stars with a minimum of 15 solar masses. [solar mass refers to the mass of the sun, when used as a unit of mass. One solar mass is equal to 1.989 x 1030 kg
A powerful, luminous stellar explosion at the end of a massive star’s life (e.g. Kepler’s Supernova).
Nebula is a Latin word for fog or cloud.It consists of interstellar clouds consisting of Helium, Cosmic Dust, ionised gases, hydrogen as well as molecular clouds. [There are in all 5 different types of Nebulae, namely;emission nebulae, reflection nebulae, dark nebulae, planetary nebulae, and supernova remnants.
A black hole is a region in the space, in which the effect of gravity is so strong, that it lets nothing escape out f it, not even light.The region appears to be black and circular.[ There are approximately 100 billion super massive black holes]
Redshift is a phenomenon in which the spectrum of an astronomical object gets displaced towards the longer( red) wavelength.
Cosmic microwave background radiation (CMBR) is the leftover of the cosmic radiation after the big bang.
: Hubble constant is the ratio of the speed at which the galaxy is moving away from the Earth to its distance from the Earth
Motion, forces, and energy — from vectors and kinematics to momentum, energy, and pressure.
Thermal physics — particle model, temperature scales, specific heat capacity and heat transfer.
Waves — general properties, reflection/refraction, TIR, lenses and the EM spectrum.
Electricity and magnetism — charge, current, circuits, electrical power and safety.
Earth & Solar System, stars and the universe — redshift, CMBR, life cycle of stars and more.
Nuclear model, ionising radiation, decay equations and half-life.
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