1.A conductor in a train travelling at 4.0 m/s (N) walks across the train at 1.2 m/s (E) to validate a ticket. If the trian car is 4.0m wide, how long does it take the conductor to reach the other side? vog=? vom 1.2 m/s(E) (1.2/4.2) vog=vom+vmg vmg= 4.0 m/s(N) 1.2m/s(E) + 4.0m/s(N) =sqrt (1.2m/s)^2 + (4.0m/s)^2 vog 4.2m/s(N17E) =4.2 m/s Tan-1= At = 4.0m/s - 1.2m/s At = 3.3s 2. A jetski speeds across a river at 11 m/s relative to the water. The jet ski's heading is South. The river is flowing West at 5m/s. Determine the jet ski's velocity relative to the shore. vog=? vom=5m/s(W) vmg=11m/s(S vog=vom+vmg =5m/s (W)+ 11m/s(S) =sqrt (5m/s)^2 + (1m/s)^2 = 12m/s sin 90 12m/s = 24 = sin 5m/s (S24W) Therefore the answer is 12m/s (S24W =17