The outside wheels of a car, running on a circular track, are going twice as fast as the inside ones. What is the length of the circumference described by the outer wheels? The wheels are five feet apart on the two axles.
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If the length of the circumference of the track crossed by the outer wheels is L, then the radius of the outer circular track is L/(2*Pi) and the radius of the inner circular track is L/(2*Pi) - d, where d is the distance between the wheels. The circuference of the path that the inner wheels cross is, then L - 2*Pi*d. This must be twice smaller than the outer track, since the speed of the outer wheels is twice as big. We have: L 2*(L - 2*Pi*d) L 2*L - 4*Pi*d 4*Pi*d 2*L - L L 4*Pi*d L 4*3.14*5 ft 62.8 ft 62' 10'' 20 yd 2' 10''
