A) Equation relating arc length to subtended angle:
s = rθ
s = arc length, r = radius, θ = angle
Given values:
s = 6×10⁴mi = 3.168×10⁸ft, r = (2.0ft)/2 = 1.0ft
Plug in and solve for θ:
3.168×10⁸ = 1.0θ
θ = 3.168×10⁸rad
B) One revolution is equal to 2π radians, so divide θ by 2π to obtain the number of revolutions:
3.168×10⁸/(2π)
= 5.042×10⁷ revolutions