SOLUTION: can you please help me solve this problem?:
A lighthouse is located on a small island 2 km away from the nearest point P on a straight shoreline and its light makes seven revol
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A lighthouse is located on a small island 2 km away from the nearest point P on a straight shoreline and its light makes seven revol
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Question 915190: can you please help me solve this problem?:
A lighthouse is located on a small island 2 km away from the nearest point P on a straight shoreline and its light makes seven revolutions per minute. How fast is the beam of light moving along the shoreline when it is 1 km from P? (Round your answer to one decimal place.)
thank you so much Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A lighthouse is located on a small island 2 km away from the nearest point P on a straight shoreline and its light makes seven revolutions per minute.
How fast is the beam of light moving along the shoreline when it is 1 km from P?
:
The way I understand this, a point 1 km from point P on the shoreline would
form a a right triangle with the lighthouse, point P, and the point 1 km from
point P. The distance from that point to the lighthouse would be the hypotenuse.
That would also be the radius of the circle the beam of light is making at that point.
Find the hypotenuse/radius
r =
r = 2.236 km
Find the circumference
C =
C = 14.05 km the circle the beam of light is making at that point
Find the speed in km/sec
One revolution: = 8.57 sec per revolution
Speed =
S = 1.64 km/sec is the speed of the light beam at that point
