To find the width of a canal a rod is fixed vertically on the bank so as to show 17/8 m of its length. The observer, whose eye is 17/6 m above the ground retires at right angles from the canal until he sees the top of the rod in a line with the further bank. If his distance from the nearer bank is now 10 m what is the width of the canal.
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30
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(all data in meter)
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Width of canal
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way2kailash
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Answer 30.
Lets say AB is the person standing 10 m from the canal and DE be the rod on near bank. C be the point on further bank that coincides with top of the rod. In here triangle ABC is similar to triangle DEC as all angles have same measure.
Lets say AB is the person standing 10 m from the canal and DE be the rod on near bank. C be the point on further bank that coincides with top of the rod. In here triangle ABC is similar to triangle DEC as all angles have same measure.
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xilef
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Just to elaborate:way2kailash wrote:Answer 30.
Lets say AB is the person standing 10 m from the canal and DE be the rod on near bank. C be the point on further bank that coincides with top of the rod. In here triangle ABC is similar to triangle DEC as all angles have same measure.
For similar triangles, the ratio of sides are equal.
so,
(17/6)/(17/8) = (10+x)/x
x = 30
