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Two racecars are driving at constant speeds around a circular track. both cars are the same distance away from the center of the track, but car 2 is driving twice as fast as car 1. the acceleration of car 2 is ___________ the acceleration of car 1.

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If the track has circumference c miles, then and the car's speeds are x and y mi/s, then since time = distance/speed,Β 

In the same direction, the slow car has a "lead" of 1 mile which the faster car has to make up.Β 

1/(y-x) = 120Β 
1/(x+y) = 30Β 

120(y-x) = 30(x+y)Β 
120y-120x = 30x+30yΒ 
90y = 150xΒ 
y = 5/3 xΒ 


1/(x + 5/3 x) = 30Β 
8/3 x * 30 = 1Β 
80x = 1Β 
x = 1/80 mi/sec = 45 mphΒ 
y = 75 mph