SS: Ray Diagrams For Converging Lens

Trick to drawing ray diagrams for converging lens: There is one ray of light passing through the center of the lens. Always. 2 rays are enough to determine the position of image/object. The other ray of light ALWAYS passes through the focal point of the lens. Either the first focal point of the second focal point. If a ray passes …

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Derivation of geodesic deviation equation

Question: Let $x^{a}$ be a geodesic, and $x^{a} + \epsilon^{a}$ be a neighbouring geodesic such that $\epsilon^{a}$ is infinitesimal. Prove the so-called geodesic deviation equation: $\frac{D^{2} \epsilon^{a}}{D \tau^{2}} = \, – R^{a}_{\: bcd} \epsilon^{c} \frac{dx^{b}}{d \tau} \frac{dx^{d}}{d \tau}$   Relevant Geodesic equations: $\frac{d^{2} x^{a}}{d \tau^{2}} + \Gamma^{a}_{\: bc} \frac{dx^{b}}{d \tau} \frac{d x^{c}}{d \tau} = 0$        — Eqn …

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Should I study physics in university?

Am I suitable to study physics in university? Should I study physics in the university? What can I expect to encounter as a physics major? How is physics in the university like? I am sure these questions are on the mind of any potential physics undergraduate. This post is meant to give you a rough idea of physics in university …

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About this site – Learn Physics online

This website (Mini Physics) offers O and A Level physics revision notes for you to learn Physics online. O Level is equivalent to American High School Diploma and A Level is equivalent to Advanced Placement. If you spot any mistakes in my explanation, please contact the site administrator at Contact Us with the relevant web address and explanation. If you feel …

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O Level Physics

Revision notes for O level Physics coursework The notes available here are great for revision and studying on the go. The O Level Physics content here is equivalent to the Physics required to obtain American high school diploma. If this is too basic for you, you can read up on A Level Physics (equivalent to Advanced placement) Most of the …

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Energy

Energy of a system is defined as its capacity to do work. (Note: Work is covered in the next sub-topic) SI unit : joules (J) Scalar Quantity; Energy has magnitude only. Principle of Conservation of Energy The Principle of conservation of energy states that energy cannot be created nor destroyed in any process. Total amount of energy of a closed system …

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