Unit 4 Revision Checklist

Unit 4: Check List Further Mechanics – Momentum: 

Definition of momentum

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Formula for momentum

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Units of momentum

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What type of quantity is momentum

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Law of conservation of momentum in collisions

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Definition of impulse

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The impulse – momentum equation

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Units for impulse

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Explanation of why an average force acts during the transfer of impulse

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Newton’s 2nd Law and rate of change of momentum

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Momentum – kinetic energy equation derivation

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Elastic and inelastic collisions

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Calculations involving conservation of kinetic energy

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Momentum in two dimensions

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If a heavy mass collides with a lighter mass at rest then angle between two collisions is less than 90

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If a light mass collides with a heavier mass at rest then angle between two collisions is more than 90

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If same masses collide with one mass at rest then angle between two collisions is equal to 90

Further Mechanics – Circular Motion: 

Understand what is a radian

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Conversion of degrees to radians and vice versa

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Angular displacement : definition and formula

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Angular velocity/speed: definition and formula

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Relationship between angular velocity and linear velocity and its derivation

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Conversion of rev/sec, rev/min to rad/sec

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Remember time period (T) for geostationary orbits is 24 hours

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Centripetal acceleration formula (two of them) (Definition or derivation not required)

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Centripetal force formula (two of them)

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Understand and explain how centripetal force combines Newton’s 1st and 2nd Laws in it

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Understand and explain why a body moving in a circle with a constant speed has acceleration

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Understand and explain why no work is done on body moving in a circle

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Understand that centripetal force is not a new or special kind of force rather it is provided by some known force

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Remember different situations where which force provides the centripetal force and explain where does the centripetal force come from: For instance, the centripetal force on the Moon is provided by the gravitational force of the Earth on the Moon.

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Understand how the formula for centripetal force varies for different positions in a vertical circular motion

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Understand what happens to the component of tension in a conical pendulum

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Unit 4: Check List Electric and Magnetic Fields – Electric Fields: 

Understand that a field is a region where a force acts

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Understand that “like” charges repel and “unlike” charges attract

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Understand the definition of electric field strength as the force per unit charge

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Understand that all fields are vector quantity and electric field strength has a direction

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Formula for electric field strength

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Units for electric field strength

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Using formula for electric field strength to find out the force

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Understand what is a uniform electric field and how to produce it

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Formula for electric field strength between two parallel plates

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Understand the concept of equipotential and equipotential lines

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Understand what is the volt

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Formula for work done to move a charge between two equipotential lines

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Understand what are radial electric fields

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Formula for electric field strength E a distance r from a point charge Q is

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Formula for Coulomb’s Law

Electric and Magnetic Fields – Capacitance: 

Explain what is capacitance

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Formula for capacitance

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Formula for energy stored by capacitors

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Explain why there is a half in the energy equation for capacitors

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Understand there are different types of capacitors, e.g. variable capacitors, electrolytic capacitors, etc.

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Know and explain the graphs for V, I and Q for charging and discharging capacitors

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Know what is the coulombmeter

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Understand exponential decay and how a graph is showing exponential decay if the ratios of the values after successful time intervals are constant

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Understand capacitor discharge relationship I Q

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Understand what is the significance of the time constant

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Formula for time constant

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Understand that a capacitor is charged or discharged completely after five time constants

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Understand how 37% of the charge remains after one time constant

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Formula for half-life of capacitor discharge:

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Understand the uses of capacitors in applications such as smoothing capacitors and flash guns.

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Understand the similarities between capacitors and springs.

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Unit 4: Check List Electric and Magnetic Fields – Magnetic Fields: 

Draw magnetic field lines of current into and out of the page

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Draw magnetic field lines around a magnet

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Understand that there are no separate North or South pole; they are always found together

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Understand the concept of neutral point in magnetic fields

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Formula for force on a current carrying conductor in a magnetic field F = BIl

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Explain how two current carrying conductors can attract or repel depending on the direction of the current in them

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Remember magnetic flux density is B and is measured in Tesla (T)

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Total magnetic flux is

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Formula for total magnetic flux is

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Units for total flux

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Understand that the Fleming’s Left Hand Rule is used to find the direction of the force in F = BIl

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Draw the path of electron beams under a magnetic field

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Explain and understand how d.c. electric motors work

Electric and Magnetic Fields – Electromagnetic Induction: 

Understand what is electromagnetic induction

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Formula for the emf induced

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Explain what is Faraday’s Law

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Explain what is Lenz’s Law

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Difference between the formula for Lenz’s and Faraday’s Law

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Explain how Lenz’s Law is explained by the law of conservation of energy

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Explain how the transformer works

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Use the Right Hand Grip Rule to find the direction of poles in a solenoid

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Use the Right Hand Grip Rule to find the direction current around a wire

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Use Fleming’s Right Hand Rule to find out the current in wire in a magnetic field

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Unit 4: Check List Particle Physics– Probing matter: 

Understand what is proton number, neutron number and nucleon number

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Explain what are isotopes

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Know how to represent an element symbol

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Clearly write down the observations and conclusions from the alpha scattering experiment

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Understand what is thermionic emission

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Understand the wave – particle duality and the equation relating them

Particle Physics– Accelerators: 

Explain how a linear accelerator works

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Explain how the time is kept constant inside in each drift tubes by increasing their length in a LINAC

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Explain how a cyclotron works

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Explain how the radius of the particle increases as the particle gains speed with necessary equation

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Workout the frequency of the radiation emitted from a cyclotron

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Explain how a synchrotron works

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Understand the cause for synchrotron radiation

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Know how to use different units of energy and mass such as Mev/c2, the unified atomic mass u, etc.

Particle Physics– Detecting particles: 

Understand how a bubble chamber or cloud chamber works

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Understand how different tracks are produced by particles for example, how spiral tracks are produced

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Explain why tracks split apart in spirals or straight lines

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Explain why tracks may be perpendicular

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Explain the shape of tracks for alpha, beta and gamma particles.

Particle Physics– Particle interactions and classification: 

Understand what are particles and antiparticles

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Understand and explain what is pair production and pair annihilation

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Understand what is rest mass and rest energy

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Understand the significance of the electron-volt (eV)

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Explain and have a clear definition of what are leptons, baryons, mesons and quarks

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Remember the charges for different leptons

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Understand baryon numbers, lepton numbers and strangeness

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Remember the different charges for the different types of quarks and their strangeness

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Understand and remember the beta particle interaction

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Understand conservation laws and use them to find out whether a particle interaction is valid or not

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Understand what is the standard model for particles

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Remember the different exchange particles for the four fundamental forces and their range of action over the forces

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