The Standard
Assignments
Motion
Mainly a recap of level 1 Mechanics; speed, acceleration, balanced and unbalanced forces. If you didn't do so well in level 1 Mechanics you should take this opportunity to go through some old level 1 past papers to bring yourself up to speed.
Otherwise here is a video showing a large range of different motions:
Otherwise here is a video showing a large range of different motions:
Forces
Unbalanced forces cause acceleration. This is one of the most important concepts of Mechanics. The following two simulations demonstrate the effect of different sized forces on different objects. They also show how to draw free body or force diagrams.
The following two videos expand on the concepts covered in class. One answers a popular question and the other covers many of the misconceptions surrounding falling objects.
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Vectors & Scalars
The following definitions come from: http://www.bbc.co.uk/bitesize/higher/physics/mech_matt/vectors/revision/3
Vectors
Vector quantities have both magnitude (size) and direction
Scalars
Scalar quantities have only magnitude (size)
Vectors
Vector quantities have both magnitude (size) and direction
Scalars
Scalar quantities have only magnitude (size)
Graphs of motion
This simulation allows you to observe distance-time, velocity-time and acceleration-time graphs in real time. This is a great tool for seeing the shape of these graphs and how they change in relation to one another during different types of motion.
Kinematic Equations
The Physics Classroom has great explanations about what the kinematic equations are, where they come from and how to use them. Here are their tips on how to answer a question that requires kinematic equations:
- Construct an informative diagram of the physical situation.
- Identify and list the given information in variable form.
- Identify and list the unknown information in variable form.
- Identify and list the equation that will be used to determine unknown information from known information.
- Substitute known values into the equation and use appropriate algebraic steps to solve for the unknown information.
- Check your answer to insure that it is reasonable and mathematically correct (does your answer seen reasonable?)
Vector Addition & Subtraction
A useful tool for carrying out vector addition of two or more vectors. Some of the techniques may be different to what you use in class.
It is harder to find good sources of information explaining how to do vector subtraction. Vector subtraction is important when trying to work out the change in a vector value, for example the change in velocity.
This Maths is Fun website has some good examples of how to do vector subtraction (and some more advance vector mathematics that you don't need to worry about). These animations show both vector addition and vector subtraction. |
Projectile Motion
Another great simulation. This time for investigation projectile motion.
Doc Physics has a great YouTube channel showing worked examples for lots of different aspects of Physics including projectile motion.
He is from the States so there are some slight differences in the symbols that he uses compared to us. For example in this playlist he use v for final velocity and vo for initial velocity (the velocity at t = 0). |
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Circular Motion
If an object is travelling in a circle its direction of motion is constantly changing this means it must be accelerating, even if it is travelling at a constant speed.
Circular motion (at a constant speed) requires an unbalanced force towards the centre of the circle. Have a play with this simulation, get the ladybug to travel in a circle and observe the direction of the unbalanced force. |
Torque
Momentum & Collisions
Momentum is a very important concept in physics, especially when dealing with collisions and explosions. Coming straight from Newton's 3rd law, every action has an equal and opposite reaction, we get conservation of momentum:
Total momentum is conserved during a collision or explosion, unless an outside force is acting.
Here we have:
Total momentum is conserved during a collision or explosion, unless an outside force is acting.
Here we have:
- A video showing conservation of momentum with no external forces acting (kind of), on the international space station
- A simulation showing momentum vectors of different objects during collisions. At level 2 you only have to cover momentum in 1D, i.e. left and right, like a train on a track.
- Hard to imagine all collisions taking time. Check out this high speed footage of a golf ball hitting a metal plate. The less time it takes of an object to change momentum (impulse) the greater the force required.
Energy
Another thing that is conserved is energy... but energy can change forms from one type to another, so not the first thing to think about when dealing with collisions and explosions. None the less, a fundamental concept of physics and our Universe. The main conversions we will look at at level 2 is Gravitational Potential Energy to Kinetic Energy and back.
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Power
Simple how quickly energy is transformed.