Combined Physics 5086 Formulae List

1 Science(Physics) 5086 List of Formulae 1. Measurement Corrected reading = Observed reading – (Zero error) 2. Kinematics t dv= v: speed [m/s] or [ms-1] d: distance [m] t: time [s] timetotal distance totalspeed Average = Average speed [m/s] total distance [m] total time [s] t uva −= a: acceleration [m/s2] or [ms-2] v: final velocity [m/s] t: time taken [s] u: initial velocity [m/s] Distance travelled = Area under Speed-Time graph 4. Forces & Pressure mgW= W: weight [N] m: mass [kg] g: acceleration due to gravity [m/s2] V mρ= ρ : density [kg/m3] m: mass [kg] V: volume [m3] volumetotal mass totaldensity Average = Average density [kg/m3] total mass [kg] total volume [m3] A Fp= p: pressure [Pa] or [N/m2] F: force [N] A: area [m2] 4. Forces and Pressure maFR = FR: resultant or net force [N] m: mass [kg] a: acceleration [m/s2] 5. Turning Effect of Forces M = F d M: moment of a force about a pivot [Nm] F: force [N] d: perpendicular distance from the line of action of the force to the pivot [m] Principle of moments: Sum of Anti-clockwise Sum of Clockwise Moments Moments F1 d1 + F2 d2 = F3 d3 + F4 d4 6. Energy, Work and Power GPE = mgh GPE: gravitational potential energy [J] m: mass [kg] g: acceleration due to gravity [m/s2] h: height raised [m] 2mv2 1KE= KE: kinetic energy [J] m: mass [kg] v: speed [m/s] W = F s W: Work done [J] F: force [N] s: distance moved in the direction of the force [m] t WP= or t FsP = or t EP= P: power [W] W: work done [J] E: energy [J] t: time [s] 7. Kinetic Model of Matter 8. Thermal Processes 9. General Wave Properties T 1=f f: frequency [Hz] T: period [s] F1 d1 F4 F2 d3 F3 = d2 d4

2 Wave velocity equation: f=v v: speed of wave [m/s] f: frequency [Hz]  : wavelength [m] Reflection of Sound: For determination of speed of sound using echo method: t 2dv= v: speed of sound [m/s] d: one-way distance [m] t: time taken for echo to be received [s] 10. Electromagnetic Spectrum 11. Light Angle of incidence = Angle of reflection Snell’s Law: r i sin sinη= or 1 1 2 2η sin η sinθθ= η : refractive index of a medium i: angle of incidence (in the vacuum or air) [o] r: angle of refraction (in the medium) [o] v cη= η : refractive index of a medium c: speed of light in vacuum or air = 3.0  108 m/s v: speed of light in the medium [m/s] 15. Electric Charge & Current Electricity Q = I t Q: charge [C] I: current [A] t: time [s] Q Wε= ε : electromotive force, e.m.f. [V] W: work do