Physics end of year exam advice 2014 - end of year exam advice 2014 ... The formula sheet only lists some of the formulas for each ... A+ Physics Units 3 4 Exam Book and co-author of A+ Physics ...

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<ul><li><p>Physics end of year exam advice 2014 </p><p>Start preparing your notes now, by Craig Tilley </p><p>The Physics examination tests units 3 &amp; 4. Topics are Motion in one and two dimensions and </p><p>Electronics and photonics (covered in the Herald Sun article 6th</p><p> May 2014), Electric Power and </p><p>Interactions of light and matter, then one of six Detailed Studies. Total is 150 marks in 150 minutes </p><p>so pace yourself and try to leave some time to check your answers. </p><p>You are allowed one folded A3 sheet or two taped A4 sheets of notes and one scientific calculator </p><p>in the exam. Start preparing your notes now. Use the VCAA formula sheet, or download one - it is </p><p>at the back of last years exam PDF. Have this handy when you start drafting your notes. VCAA </p><p>number the formulas, but they are grouped by topic and there is some overlap between topics. </p><p>Generally: formulas 1-11 go with Motion in one and two dimensions, 12-14 go with Electronics and </p><p>Photonics, 15-19 go with Electric Power, 20-28 go with Interactions of light and matter. Then the </p><p>Detailed Studies follow with 29-33 going with Synchrotron and its applications, 34 &amp; 35 go with </p><p>Photonics, 36 is for Sound, 37-41 go with Einsteins special relativity, 42-44 go with Materials and </p><p>their use in structures and formula 45 goes with Further Electronics. Formulas 46 to 51 may be used </p><p>by different topics. </p><p>The formula sheet only lists some of the formulas for each topic. To draft your notes, work through </p><p>some past VCAA papers or the commercial ones bought by your school, or the A+ Exam practice </p><p>book. Attempt a question and identify the topic: Motion in one and two dimensions, Electronics and </p><p>photonics etc. Try to get the answer using your existing knowledge, dont look anything up yet. If </p><p>you can, thats good news. Correct your answer from the solutions. If you cant do the question, this </p><p>tells you something and its good news too. Learn from it. Consult the solution and work out what it </p><p>tells you. Add any formulas to your draft notes under the topic heading. Any concepts you didnt </p><p>recall? Add them to your notes too. Continue with the next question. Dont try to do a whole exam </p><p>in a set amount of time just yet, thats for closer to exam time. Doing questions and adding to your </p><p>notes is one of the best ways to study Physics (and other subjects too)! So, keep going. Get more </p><p>past and trial papers. Revise your notes from time to time and delete anything you remember well to </p><p>make more space. It is a work in progress and might not be finished until right before the exam. </p><p>Now to complete my Unit 4 advice for this year. </p><p>Electric Power </p><p>To determine the magnetic field direction at a point, determine the field from each magnet </p><p>separately and add as vectors. </p><p>Voltage from a generator is given by Faradays law and current direction is given by Lenzs law. </p><p>The direction of induced current has three steps: </p><p>1. What flux change is occurring? </p><p>2. What would oppose this (or restore the original)? </p><p>3. Hence what is the current direction? </p><p>DC motors and generators utilise a split ring commutator while AC utilise slip rings. </p><p>A shape of a voltage-time graph follows the negative gradient of the flux-time graph. </p><p>Transmission lines form series circuits with long wires that lose voltage and power. The voltage of </p><p>the power supply (e.g. 200 V) is lost along the sum of both lines and the output (e.g. 12 V along </p></li><li><p>each transmission line and 176 V at the load). Power values follow the same pattern. Current is the </p><p>same in each. </p><p>Interactions of light and matter </p><p>Use h = 4.14 1015 </p><p>for electron volt energy (eV). Otherwise use h = 6.63 1034 </p><p>Js. For </p><p>momentum h = 6.63 1034 </p><p>Js &amp; energy must be in joules (J). </p><p>Energy level diagrams: longest wavelength will have lowest energy and lowest frequency. Shortest </p><p>wavelength will have highest energy and highest frequency. </p><p>Photoelectric effect involves energy. Incident light has energy (hf), and if above the minimum for </p><p>the electrons (W), any excess energy becomes the electrons kinetic energy (KEmax). </p><p>So: hf = W + KEmax </p><p>And: hf = hfo + qVo where fo = threshold frequency &amp; Vo = stopping voltage. </p><p>If light intensity increases, everything stays the same, simply more current flows. </p><p>If light frequency increases, light energy &amp; KEmax increase, W remains the same. </p><p>If the metal changes, f stays the same, W changes &amp; so KEmax changes. </p><p>If f &lt; fo ; Elight &lt; W so no photoelectrons are ejected. </p><p>In Youngs experiment the central max is bright as PD = 0. Other maximums are bright as PD = n. </p><p>Minima are dark as PD = (n ) . The n number is the line number from the central maximum </p><p>where n = 0. The band spacing (x) is determined from: x ( L) / d and x L / (f d). </p><p>Electron diffraction compares to X-ray diffraction if the electrons de Broglie wavelength compares </p><p>to the X-ray wavelength. Electrons have NO frequency &amp; do NOT travel at c. Wavelength and </p><p>momentum are linked for electrons but NOT wavelength and energy. </p><p>Craig Tilley has been a Physics examination assessor for over 15 years and is the author of the </p><p>A+ Physics Units 3 &amp; 4 Exam Book and co-author of A+ Physics Notes. </p></li></ul>


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