Physics 2 Calculation of Kinetic and Potential Energy PDF
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This document provides calculations for kinetic and potential energy, including examples and formulas. It covers different types of potential energy and mechanical energy conservation in various scenarios, like roller coasters and pendulums.
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## Calculate Kinetic/Potential Energy - Kinetic - all objects in motion (moving) ### Kinetic Energy Formula $EK = 0.5mv^2$ Where: * $EK$ = Kinetic Energy * $m$ = Mass * $v$ = Velocity ### Example Calculation * $EK$ = ? * $m$ = 0.155 kg * $v$ = 12.4 m/s $EK = 0.5(0.155)(12.4)^2 = 12.44 J$ ##...
## Calculate Kinetic/Potential Energy - Kinetic - all objects in motion (moving) ### Kinetic Energy Formula $EK = 0.5mv^2$ Where: * $EK$ = Kinetic Energy * $m$ = Mass * $v$ = Velocity ### Example Calculation * $EK$ = ? * $m$ = 0.155 kg * $v$ = 12.4 m/s $EK = 0.5(0.155)(12.4)^2 = 12.44 J$ ## Potential Energy Types - Potential - Object due to gravity (gravity/height) - Electric - measure of Ep in 2 or more charged particles - Elastic - compressed energy (Spring) - Chemical - energy held in bonds between atoms/compounds ## Difference in Potential Energy (ball dropped from chair to desk) ### Potential Energy Calculation $EP = mgh$ Where: * $EP$ = Potential Energy * $m$ = mass * $g$ = acceleration due to gravity * $h$ = height ### Example Calculation: * $EP$ = ? * $m$ = 105 kg * $g$ = 9.81 m/s² * $h$ = 100 m $EP = (105)(9.81)(100) = 103,005 J$ ### Example Calculation: * $EP$ = ? * $m$ = 105 kg * $g$ = 9.81 m/s² * $h$ = 38 m $EP = (105)(9.81)(38) = 39,142 J$ ### Difference in Potential Energy: $103,005 - 39,142 = 63,893 J$ ## Calculate Mechanical Energy - Mechanical Energy never changes, always stays the same. $Em = 0.5mv^2 + mgh$ ## Example Calculation: * $Em$ = ? * $m$ = 6.42 kg * $v$ = 2.46 m/s * $g$ = 9.81 m/s² * $h$ = 1.5 m * $F$ = 63N $Em = 0.5(6.42)(2.46)^2 + (6.42)(9.81)(1.5) = 113.9 J$ ## Kinetic, Potential, Mechanical in Roller Coasters & Pendulums ### Pendulum #### Point A * $Em$ = $EP + EK$ * $Em$ = $0.5mv^2$ * $m$ =0.0253 kg (25.3g converted to kg) * $v$ = 7.5 m/s * $Em$ = 0.5(0.0253)(7.5)² = 0.71 $J$ #### Point B * $Em = EP + EK$ * $Em = mgh$ * $m$ = 0.0253 kg * $g$ = 9.81 m/s² * $h$ = ? * $0.71$ (energy is conserved) * $h$ = 2.86 m ### Roller Coaster #### A * $Em = EP$ * $m$ = 105 kg * $g$ = 9.81 m/s² * $h$ = 100 m * $Em$ = 103,005 $J$ #### B * $Em = EP + EK$ * $Em$ = $Em$ * $Em$ = 103,005 - 44.19 $J$ * $v$ = 44 m/s
