Ib Physics Hl Study Guide Graded A+

Spectral classes {Ans: We can measure the wavelength of light emitted from a star and from it deduce the colour in the EM spectrum that this corresponds to. In this way we classify stars into 'Spectral Classes'. The spectral classes are (in order of descending surface temperature) O,B,A,F,G,K,M with respective colours blue, blue-white, white, yellow-white, yellow, orange, orange-red.}Horizontal component of projectile motion {Ans: The horizontal velocity is constant as there is no force and therefore no acceleration in the horizontal direction.}Gas laws {Ans: At a constant V, PαT - Pressure law At a constant P, VαT - Charles' Law At a constant T, P α(1/V) - Boyles Law}Newton's assumptions about the universe {Ans: that it is infinite, uniform and static}Ideal gas equation {Ans: PV=nRT where P = pressure, V= volume, n = number of moles, R = the molar gas constant and T = temperature.}Period {Ans: Time taken for one complete oscillation (T = 1/f)}Huygen's principle {Ans: The principle that any point on a wave front of light may be regarded as the source of secondary waves and that the surface that is tangent to the secondary waves can be used to determine