Geostationary Orbits Many communication satellites around Earth follow a?geostationary orbit This is a specific type of orbit in which the satellite: Remains directly above the equator, therefore, ...
Circular Orbits in Gravitational Fields Since most planets and satellites have a near circular orbit, the gravitational force?FG?between the sun or another planet provides the?centripetal force?nee...
Newton's Law of Gravitation The gravitational force between two bodies outside a uniform field, e.g. between the Earth and the Sun, is defined by Newton’s Law of Gravitation Recall that the mass of...
Defining Gravitational Field There is a force of attraction between?all?masses This force is known as the ‘force due to gravity’ or the weight The Earth’s gravitational field is responsible for the...
Calculating Centripetal Force An object moving in a circle is not in equilibrium, it has a resultant force acting upon it This is known as the?centripetal force?and is what keeps the object moving ...
Calculating Centripetal Acceleration Centripetal acceleration is defined as: The acceleration of an object towards the centre of a circle when an object is in motion (rotating) around a circle at a...
What Causes Centripetal Acceleration? Velocity?and?acceleration? are both?vector? quantities An object in?uniform circular motion?is?continuously changing direction,?and therefore is?constantly cha...
Angular Speed Any object travelling in a uniform circular motion at the same speed travels with a?constantly changing velocity This is because it is?constantly changing direction, and is therefore ...
Radians & Angular Displacement In circular motion, it is more convenient to measure angular displacement in units of?radians?rather than units of degrees The?angular displacement?(θ) of a body ...
多數人，留學為了學習更專業的知識、國際化的視野，更好的職場發展。其中，留學專業的選擇在一定程度上決定了你的選校范圍，甚至是畢業以后你的職業選擇范圍。那么，留學美國專業選什么好？怎么選？ 美國留學特點...
Quark Composition: Protons & Neutrons Protons and neutrons are?not?fundamental particles. They are each made up of three quarks Protons?are made up of?two up quarks and a down quark Neutrons?ar...
Fundamental Particles: Quarks Quarks are?fundamental particles?that make up other subatomic particles such as?protons and neutrons Protons and neutrons are in a category of particles called?hadrons...
