A street light bulb is fixed on a pole 6 m above the level of the street. If a woman of height 1.5 m casts a shadow of 3m, find how far she is away from the base of the pole
Solution:
Given, a street light bulb is fixed on a pole 6m above the level of the street.
Also, a woman of height 1.5 m casts a shadow of 3 m.
We have to find the distance between the woman and the base of the pole.
Let PQ be the height of street light bulb = 6 m
Let CD be the height of the woman = 1.5 m
Let ED be the shadow of the woman = 3 m
Let DQ be the distance between the woman and the base of the pole = x m
In △CDE and △PQE,
∠E = ∠E = common angle
∠D = ∠Q = 90°
AAA criterion states that if two angles of a triangle are respectively equal to two angles of another triangle, then by the angle sum property of a triangle their third angle will also be equal.
By AAA criterion, △CDE ⩬ △PQE
By the property of similarity,
The corresponding sides are proportional.
So, ED/EQ = CD/PQ
3/(3 + x) = 1.5/6
3(6) = 1.5(3 + x)
18 = 4.5 + 1.5x
1.5x = 18 - 4.5
1.5x = 13.5
x = 13.5/1.5
x = 9 m
Therefore, the woman is at a distance of 9 m from the base of the pole.
✦ Try This: A street light bulb is fixed on a pole 8 m above the level of the street. If a woman of height 2 m casts a shadow of 3.8m, find how far she is away from the base of the pole.
☛ Also Check: NCERT Solutions for Class 10 Maths Chapter 6
NCERT Exemplar Class 10 Maths Exercise 6.4 Problem 8
A street light bulb is fixed on a pole 6 m above the level of the street. If a woman of height 1.5 m casts a shadow of 3m, find how far she is away from the base of the pole
Summary:
A street light bulb is fixed on a pole 6 m above the level of the street. If a woman of height 1.5 m casts a shadow of 3m, she is 9 m away from the base of the pole
☛ Related Questions:
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