You wish to cross the 11 m x 10 m courtyard without being detected by the two guards and escape through a door located on the western wall. Guard 1 is located in a tower at the northeast corner of the yard and Guard 2 is located in the yard, in the southwest corner, as shown in the figure below. Guard 1 can hear you if anything more than 1/36 of the footstep sound energy reaches them; similarly Guard 2 can hear you if anything more than 1/16 of the footstep sound energy reaches them (Guard 1 can hear more due to his elevated height in the tower). Assume for now that both guards are fixed at these locations and cannot move unless they detect you.
You wish to cross the 11 m x 10 m courtyard without being detected by the two guards and escape through a door located on the western wall. Guard 1 is located in a tower at the northeast corner of the yard and Guard 2 is located in the yard, in the southwest corner, as shown in the figure below.
Guard 1 can hear you if anything more than 1/36 of the footstep sound energy reaches them; similarly Guard 2 can hear you if anything more than 1/16 of the footstep sound energy reaches them (Guard 1 can hear more due to his elevated height in the tower). Assume for now that both guards are fixed at these locations and cannot move unless they detect you.
Now assume that Guard 2 is on patrol. He walks a straight patrol route up and down along the dotted line always remaining 3 m from the western wall. Determine the new maximum safe distance between the two hearing zones of the guards for you to pass undetected? (Hint: use Pythagorean Theorem or distance formula)
Where is the Guard 2 located for the maximum distance between the guards to occur? (at the northern or southern wall?)____________. In this case, the red dot for Guard 2 is shifted from location (3,3) to ____.
When this happens the distance between the guards is: ________________.
Therefore, the maximum safe distance is:___________ .
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