Converging & Diverging Lenses A lens is a piece of equipment that forms an image by refracting light There are two types of lens: Convex Concave Convex Lenses In a convex lens, parallel ...
Measuring Refractive Index Aim of the Experiment To investigate the refraction of light through a perspex block Equipment Ray Box - to provide a narrow beam of light to refract through the perspex ...
Total Internal Reflection Total internal reflection (TIR) occurs when: The angle of incidence is greater than the critical angle and the incident refractive index n1 is greater than the refractive ...
Critical Angle As the angle of incidence is increased, the angle of refraction also increases until it gets to 90° When the angle of refraction is exactly 90° the light is refracted along the bound...
Refraction & Refractive Index Refraction occurs when light passes a boundary between two different transparent media At the boundary, the rays of light undergo a change in direction and a chang...
Equation for the Intensity of Radiation Progressive waves transfer energy The amount of energy passing through a unit area per unit time is the intensity of the wave Therefore, the intensity is def...
Core Practical 7: Investigating Stationary Waves Aims of the Experiment The overall aim of the experiment is to measure how the frequency of the first harmonic is affected by changing one of the fo...
Wave Speed on a Stretched String The speed of a wave travelling along a string with two fixed ends is given by: Where: T = tension in the string (N) μ = mass per unit length of the string (kg m–1) ...
Stationary Waves Stationary waves, or standing waves, are produced by the superposition of two waves of the same frequency and amplitude travelling in opposite directions This is usually achieved b...
Phase & Path Difference Waves are said to be coherent if they have: The same frequency A constant phase difference Phase Difference Two points on a wave, or on different waves, are in ph...
Interference & Superposition of Waves Interference occurs whenever two or more waves combine to produce a resultant wave with a new amplitude Superposition literally means to be positioned over...
各国数学赛事的新赛季时间陆续敲定，除了广受关注的AMC系列、UKMT系列赛事，加拿大的COMC赛事也是大家证明实力、丰富学术背景的选项之一，同样值得同学们关注！ COMC将于今年10月底举行，此刻正是备赛的黄金阶段...
