P3 – Things to know
P3.1 Medical applications of physics
Refraction
To know Refraction is the change of direction of light as it passes from one medium to
another.
To know the formulae to calculate Refractive index
Refractive index = sin i
sin r
Lenses – Convex and Concave
To know what is meant by the focus and focal length of lenses.
To understand the terms ‘real’ and ‘virtual’ as applied to images.
To be able to explain how a lens refracts light to form images
To know how images are formed in convex and concave lenses
To be able to draw ray diagrams for converging and diverging lenses
To know how to calculate the magnification of an image
The Eye
To know the structure of the eye
To be able to link structure of the eye to function
To understand how concave and convex lenses can be used to correct vision
To know the near point and far point of an eye
To know how the structure of the eye can be compared to the structure of the camera
To be able to calculate the power of lens using P = 1/f
Other uses of light
To know the meaning of the terms total internal reflection and critical angle
To understand the concept of total internal reflection and critical angle.
To understand and use the relationship between refractive index and critical angle.
To be able to calculate Refractive index using the formula
Refractive index = 1
Sin c
To know the uses of lasers and TIR
X-Rays
To know the properties and uses of X-Rays
To know risks and safety precautions for X-rays
To compare CT scans to X-rays
Ultrasound
To know the definition of ‘ultrasound’.
To know the medical uses of ultrasound
To know how to calculate distance using ultrasound echoes
To understand the advantages and disadvantages of using Ultrasound, X-Rays or CT scans in
terms of safety and quality of image formed.
P3.2 Using physics to make things work
Centre of mass
To understand the term Centre of mass
To be able to analyse the stability of objects by evaluating their tendency to topple.
To know simple applications of pendulums
To be able to calculate the time period for a Pendulum using the formula
T = 1/f
Moments
To know how to calculate Moments
To understand the principle of conservation of moments
To be able to calculate Force and moments using the equation
To know definitions for pivots and levers
To understand the importance of using levers in everyday objects
Hydraulics
To know how to calculate pressure using the formula P=F/A
To be able to calculate pressure at different parts of a hydraulic system
To understand the action of a hydraulic machine
To Understand that a force exerted at one point on a liquid will be transmitted to other
points in the liquid.
Circular motion
To be able to identify which force(s) provide(s) the centripetal force in a given situation.
To know how mass, speed and radius of a circle are affected by centripetal force
To understand why an object in circular motion accelerates towards the centre of the circle,
and what is meant by centripetal force.
P3.3 Keeping things moving
The Motor effect
To know Fleming’s left hand rule
To be able to use Fleming’s Left-hand Rule to identify the direction of the force on a current
carrying conductor.
To understand the principle of the motor effect
To know how the size and direction of the force produced can be altered.
Transformers
To understand the principle of electromagnetic induction
To know and understand the structure of the transformer.
To be able to explain how a transformer works
To know and understand the difference between a step-up transformer and a step-down
transformer.
To be able to use the transformer equation.
To understand the difference between a switch mode transformer and a conventional
transformer.
To know the advantages and uses of switch mode transformers.