A boy of height 1.5, m with his eye level at | vedclass

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(C) Let the boy stand at a distance $d$ from the mirror. The eye level is at $1.4\, m$ from the ground. The mirror extends from $0.8\, m$ to $1.55\, m

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the boy cannot see his feet

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(C) Let the boy stand at a distance $d$ from the mirror. The eye level is at $1.4\, m$ from the ground. The mirror extends from $0.8\, m$ to $1.55\, m$ $(0.8 + 0.75)$ above the ground.$1$. To see the top of his head (hair): The ray from the top of his head $(1.5\, m)$ must strike the mirror at its top edge $(1.55\, m)$. Since the eye is at $1.4\, m$ and the top of the mirror is at $1.55\, m$,the ray can easily reach the eye. Thus,the boy can see his hair.$2$. To see his feet: The ray from his feet $(0\, m)$ must strike the mirror at some point $y$ and reflect to the eye $(1.4\, m)$. By similar triangles,the height $y$ on the mirror required to see the feet is $y = \frac{1.4}{2} = 0.7\, m$ from the ground. However,the lower edge of the mirror is at $0.8\, m$. Since $0.7\, m < 0.8\, m$,the ray from the feet cannot reach the mirror. Therefore,the boy cannot see his feet.

$A$ boy of height $1.5\, m$ with his eye level at $1.4\, m$ stands before a plane mirror of length $0.75\, m$ fixed on the wall. The height of the lower edge of the mirror above the floor is $0.8\, m$. Then:

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