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Physics CAT

[highlight] [b]Distance, Speed, Time and Acceleration[/b] [code] Speed = Distance [divide] Time Acceleration = (v - u) [divide] t (v = final velocity [b]Speed with direction[/b], u = begin velocity, t = time) [/code] [/highlight] [highlight] [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 [/code] 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) [/highlight] [highlight] [b]Volts, Amperes and Resistance[/b] [code] V = I [multiply] R (V = volts, I = amps, R = resistance) [/code] Resistance is measured in Ohm's ([ohm]) [/highlight] [highlight] [b]Charge, Current and Time[/b] [code] Q = I [multiply] T (Q = charge [b]Coulombs[/b], I = amps, T = time [b]seconds[/b]) [/code] [/highlight] [highlight] [b]Wave Equation[/b] [code] V = f [multiply] [lambda] (V = wave speed, f = frequency, [lambda] wavelength) [/code] [/highlight] [highlight] [b]Sound moves at faster speeds through denser objects[/b] [/highlight] [highlight] [b]Work, Force, Distance[/b] [code] work = force [multiply] distance (work = joules, force = newtons, distance = metres) [/code] The distance can be any sort of distance at all, in metres [/highlight] [highlight] [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 [/code] [/highlight] [highlight] [b]Impact Speeds[/b] [code] v[squared] = 2(g [multiply] h) [g = gravitational field strength (N/kg), h = height (m, metres)] [/code] [/highlight] [highlight] [b]Weight[/b] [code] weight (newtons) = gravitational field strength (N/kg) [multiply] mass (kg) [/code] [/highlight] [highlight] [b]Force, mass, acceleration[/b] [code] F = m [multiply] a (F = force (N), m = mass (Kg), a = acceleration (m/s[squared])) [/code] [/highlight] [highlight] [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 [/code] [/highlight] [highlight] [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) [/code] [/highlight] [highlight] [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] [/highlight] [highlight] [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) [/highlight] [highlight] 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]