- #1
keylostman
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Homework Statement
A car engine accerlates from 1080rpm to 4800rpm in 12.5 seconds. Calculate the angular accleration, assumed constant, and the total number of revolutions the engine makes in this time
The Attempt at a Solution
angular acceleration (a) = (wf - wi) /(tf - ti)
(a) = (160 - 36) π / 12.5 = 31.15 rad/s^2
angle moved = θ = wi * t + 0.5 at^2
θ = 36 π *12.5 + 0.5 [124 π / 12.5 ] [12.5]^2
θ = 450 π + 0.5 [124 π] 12.5
θ = 450 π + 775 π = 1225 π
θ = [1225/2] [2π] = N[ 1 revolution]
N = numberof revolutions made = N = 1225/2 = 612.5
DID I DO THIS RIGHT?