Two people start at the same place and walk around a circular lake in opposite directions. One walks with an angular speed of 1.10 10-3 rad/s, while the other has an angular speed of 3.90 10-3 rad/s. How long will it be before they meet?

Answer 1

d1 + d2 = 2pi,
(1.1*10^-3)t + (3.9*10^-3)t = 2pi,
5*10^-3t = 2pi,
t = 2pi/0.005 = 6.28/0.005 = 1256 s =
20.9 min.