Problem 2-98 - Linear Kinematics - Part 4

 A helicopter is traveling horizontally, straight toward a cliff. When \(700 \;m\) from the cliff, it sends a sonar signal and \(3.4 \;s\) later receives the reflected signal. Assuming the signal travels at \(350 \;m/s\), determine the speed of the helicopter.

diagram of helicopter

Accumulated Solution

\(d = vt \\ d = (350 \;m/s)(3.4 \;s) = 1190\; m\)

You should have:

\(d = (350 \;m/s)(3.4 \;s) = 1190\; m\)

How far is the signal echo from the cliff when it meets the helicopter?

(A)   \(1190 - 700 = 490\; m\)

(B)   \(1190 + 700 = 1890\; m\)

(C)   \((1/2)(1190 + 700) = 945 \;m\)