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Using the Science Formula Page And Calculator Help The Formula Chart for Science On the science chart, the meanings of the letters in the formulas are given to you. You must know the measurement units to know what numbers fit to which letter. The box at the bottom provides some help . . . Let’s look. When you don’t know – look! Very important information is here. Example: Newton which is the unit of Force is found by multiplying kg (mass) times m/s2 which is the unit for acceleration. Example: What is the net force exerted on a 90.0 kg race-car driver while the race car is accelerating from 0 to 44.7 m/s in 4.50 s? F 9.8 N We see kg, but not m/s2, so we have to calculate acceleration first . . G 20 N Acceleration = Vf – Vi H 201 N time A = 44.7 – 0 = 9.9 m/s2 J 894 N 4.5 So F = 90.0kg x 9.9 m/s2 = 893.9 N Science questions some times give more information than is needed. Match units to formulas on the formula page. Time should be in seconds in all formulas. Mass must be in Kilograms for Force, Momentum, Work and Power. Work and energy must be in Joules or Newton-meters. This can be overwhelming if you try to wait until the day before to learn them. Try flash cards with units and what they measure. A person pushes a large box across a level floor by applying a horizontal force of 200 N. If the person pushes the box a distance of 5 XXXXXXXXXXXX meters in 10 seconds, how much work does the person do on the box? In problems with numbers; A 2000 joules B 1000 joules 1) find the question word, C 400 joules 2) look up the formula on D 100 joules the formula page, Work = force x distance No mention of time! or 200N x 5 m = 1000 joules 3) Cross out information you do not need 4) put the numbers in the CALCULATOR in order. Let’s look at some related formulas . . . The bottom equation says Speed, but uses v in the equation. According to the top formula, v means velocity. Velocity is more accurate since it is speed in one direction. On TAKS these words are used interchangeably. Momentum = mv so . . . 3 Which bike rider has the greatest momentum? A A 40 kg person riding at 45 km/h B A 50 kg person riding at 35 km/h C A 60 kg person riding at 25 km/h D A 70 kg person riding at 15 km/h 1800 1750 1500 1050 Just like on the Math test, plug in each answer and see which one works (it is the largest). . . Most important . . . Do not guess, look and calculate!!