A rod of height h = 1.25 m is placed vertically on a reflecting surface as shown in figure. Rays from sun cast shadow of rod on wall. Length of shadow on wall is (in meters) (Write upto two digits after the decimal point.)

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Solution

$t a n θ = \frac{C D}{D E} = \frac{A D}{D F}$

Shadow = DF - DE

$= \frac{A D - C D}{t a n θ} = \frac{A C}{t a n θ}$

$= \frac{2 A B}{tan θ}$
$= 2 h (∵ tan θ = \frac{A B}{h}) = 2 \times 1.25 = 2.50$

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A rod of height h = 1.25 m is placed vertically on a reflecting surface as shown in figure. Rays from sun cast shadow of rod on wall. Length of shadow on wall is (in meters) (Write upto two digits after the decimal point.)

tan θ=CDDE=ADDF Shadow = DF - DE =AD−CDtan θ=ACtan θ =2ABtan θ =2h(∵tanθ=ABh)=2×1.25=2.50

$t a n θ = \frac{C D}{D E} = \frac{A D}{D F}$

Shadow = DF - DE

$= \frac{A D - C D}{t a n θ} = \frac{A C}{t a n θ}$

$= \frac{2 A B}{tan θ}$
$= 2 h (∵ tan θ = \frac{A B}{h}) = 2 \times 1.25 = 2.50$