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[b]Distance, Speed, Time and Acceleration[/b]
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Speed = Distance [divide] Time
Acceleration = (v - u) [divide] t (v = final velocity [b]Speed with direction[/b], u = begin velocity, t = time)
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[b]Wavelength, Period and Frequency[/b]
[code]
frequency = number of oscillations (cycles) of wave [divide] time taken
frequency = 1 [divide] period
period = 1 [divide] frequency
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Frequency [b]Hz[/b] = Amount of waves passing a point in [b]x[/b] seconds (1 if undefined).
Period [b]Seconds[/b] = How long 1 wave cycle (complete oscillation takes)
Wave Length [b]([lambda])[/b] = The distance covered by a single wave (metres)
Amplitude [b]metres[/b] = Max displacement of a wave from base (the height of the curve of a wave from middle)
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[b]Volts, Amperes and Resistance[/b]
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V = I [multiply] R (V = volts, I = amps, R = resistance)
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Resistance is measured in Ohm's ([ohm])
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[b]Charge, Current and Time[/b]
[code]
Q = I [multiply] T (Q = charge [b]Coulombs[/b], I = amps, T = time [b]seconds[/b])
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[b]Wave Equation[/b]
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V = f [multiply] [lambda] (V = wave speed, f = frequency, [lambda] wavelength)
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[b]Sound moves at faster speeds through denser objects[/b]
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[b]Work, Force, Distance[/b]
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work = force [multiply] distance (work = joules, force = newtons, distance = metres)
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The distance can be any sort of distance at all, in metres
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[b]Potential Energy[/b]
Ep = Potential Energy (joules, J)
m = mass (kg)
g = gravitational field strength (N/kg)
h = height (m, metres)
[code]
Ep = m [multiply] g [multiply] h
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[b]Impact Speeds[/b]
[code]
v[squared] = 2(g [multiply] h) [g = gravitational field strength (N/kg), h = height (m, metres)]
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[b]Weight[/b]
[code]
weight (newtons) = gravitational field strength (N/kg) [multiply] mass (kg)
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[b]Force, mass, acceleration[/b]
[code]
F = m [multiply] a (F = force (N), m = mass (Kg), a = acceleration (m/s[squared]))
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[b]Kinetic Energy[/b]
Ek = Kinetic Energy (J, joules)
m = mass (kg)
v = velocity (m/s) [speed with direction, a vector quantity]
[code]
Ek = (m [multiply] v[squared]) [divide] 2
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[b]Change in gravitational potential energy[/b]
GPE = gravitational potential energy (N/kg)
w = weight (N)
h = height (m)
[code]
Change in GPE = w [multiply] (change in h)
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[b]Efficiency[/b]
[code]Ef = Uo [divide] Ti[/code]
Ef = Efficiency
Uo = Useful Output
Ti = Total Input
[i]Multiply by 100 for percentage efficiency[/i]
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[b]Power[/b]
[code]Power = Energy Change [divide] Time Taken[/code]
or
[code]Power = Work Done [divide] Time Taken[/code]
Power = Watts (W) or Joules per second
Work done = joules (J)
Time taken = seconds (s)
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Further Reading:
[link href='http://www.bbc.co.uk/education/guides/zwwmxnb/revision']Motion and Motion Graphs on the other pages[/link]
[link href='http://www.bbc.co.uk/education/guides/zyydmp3/revision/2']Newton's Laws[/link]
[link href='http://www.bbc.co.uk/education/guides/zq7thyc/revision/1']Light (Check pages 1-4)[/link][link href='http://www.bbc.co.uk/education/guides/z66g87h/revision/4']EM Spectrum (All pages)[/link]