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rgalvan2

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A child is in danger of drowning in the Merimac river. The Merimac river has a current of 3.1 km/hr to the east. The child is 0.6 km from the shore and 2.5 km upstream from the dock. A rescue boat with speed 24.8 km/hr (with respect to the water) sets off from the dock at the optimum angle to reach the child as fast as possible. How far from the dock does the boat reach the child?

https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/fall08/homework/02/IE_rescue/boat.gif

https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/fall08/homework/02/IE_rescue/help/help/help/help_t/pic6.gif

The hardest calculation in this problem is to determine the time it takes for the swimmer to be rescued (and thus the time the dock is moving).

What is t?

So I need to use Pythagorean Theorem to find z. I found it to be 2.57. Then I used d=vt to find the time it takes for the swimmer to be rescued which is the time the dock is moving. So for v, the problem says to use the boat's velocity which is 24.8. I get t=.104 hr. It keeps saying I'm wrong. What am i doing wrong? Help Please!

https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/fall08/homework/02/IE_rescue/boat.gif

https://online-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?courses/phys211/fall08/homework/02/IE_rescue/help/help/help/help_t/pic6.gif

The hardest calculation in this problem is to determine the time it takes for the swimmer to be rescued (and thus the time the dock is moving).

What is t?

So I need to use Pythagorean Theorem to find z. I found it to be 2.57. Then I used d=vt to find the time it takes for the swimmer to be rescued which is the time the dock is moving. So for v, the problem says to use the boat's velocity which is 24.8. I get t=.104 hr. It keeps saying I'm wrong. What am i doing wrong? Help Please!

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