Thursday, 8 March 2012

Equations Glossary

These are most of the equations you need to know. If I have missed any out, please comment and let me know. Thanks!

(i) the relationship between average speed, distance and time: 
average speed= distance/time
(ii) the relationship between force, mass and acceleration: 
force = mass × acceleration 
acceleration = change in velocity/time taken
(iii) the relationship between density, mass and volume: 
(iv) the relationship between force, distance and work: 
work done = force × distance moved in direction of force 
(v) the energy relationships: 
energy transferred = work done 
kinetic energy = ½ × mass × speeds2
Ek= ½ x m x s2
gravitational potential energy = mass × g × height 
(vi) the relationship between mass, weight and gravitational field strength: 
weight = mass × gravitational field strength 
W=m x g
(vii) the relationship between an applied force, the area over which it acts and the resulting 
(viii) the relationship between the moment of a force and its distance from the pivot: 
moment = force × perpendicular distance from the pivot 
moment=F x d

(ix) the relationships between charge, current, voltage, resistance and electrical power: 
charge = current × time 
voltage = current × resistance 
electrical power = voltage × current 
(x) the relationship between speed, frequency and wavelength: 
wave speed = frequency × wavelength 
V(velocity)=f x λ
(xi) input (primary voltage)/output (secondary voltage)=primary turns/secondary turns
(xii) the relationship between refractive index, angle of incidence and angle of refraction: 
n=sin i/sin r
(xiii) the relationship between refractive index and critical angle: 
sin c = 1/n
(xiv) the relationship for pressure difference: 
pressure difference = height × density × g 
p = h x ρ x g


  1. Thank you so much Michelle! You have no idea how many times I've recommended your blog to my friends! :-)

    1. You're very welcome ~ I'm so happy it's worthy of recommendation, good luck with your studies!! :) :)

  2. i will nominate you for the nobel peace prize


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Note: This blog will no longer be updated as I finished IGCSEs in 2012. Sorry! :( If you are interested in buying IB notes though, please contact me. :)