How Does Accelerating a Car Affect Its Engine's Angular Metrics?

AI Thread Summary
The discussion focuses on the effects of accelerating a car on its engine's angular metrics, specifically examining angular acceleration, tangential acceleration, revolutions, torque, kinetic energy, and angular momentum. The angular acceleration calculated is 180.12 rad/s², with a tangential acceleration of 3.42 m/s² at the crankshaft's edge. During the acceleration phase, the engine completes approximately 139.58 revolutions. The torque generated by the engine is determined to be 1.62 mN, while the kinetic energy of the crankshaft at maximum RPM is calculated to be 1492.78 J. The calculations indicate a solid understanding of the relationships between angular motion and engine performance metrics.
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As you press down on the accelerator of your car you see the tachometer climb steadily from 1200 rpm to 5500 rpm in 2.5 s.
(a) What is the angular acceleration of the car?
(b) What is the tangential acceleration of a point on the edge of the engine’s 3.8 cm diameter crankshaft?
(c) How many revolutions does the engine make during this time?
(d) If the moment of inertia of the crankshaft is 0.009 kg.m2, what is the torque generated by the engine?
(e) What is the kinetic energy of the crankshaft at its maximum rpm? What is its angular momentum at that time?


I like to make sure I'm grasping this:

angular velocity intial and final (wi and wf)
a. wi=125.66 wf=575.96
wf=wi+at
575.96=125.66-a2.5
ang=180.12 rads-2

b.ang=a/r
ang*r=a
180.12*.019=a
a=3.42 ms-2

c.theta=wit+(1/2)at^2
theta=314.14+562.88
theta=877.02 rad
rev=theta/2pi
rev=877.02/2pi
rev=139.58

d. torque=I*ang
torque=.009*180.12
torque=1.62 mN

e. K=(1/2)Iw^2
K=(1/2)(.009)(575.98(^2
K=1492.78 J
 
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