A telescope consists of two convex lenses of focal length 16 cm and 2 cm- If the object subtends an angle of 0-5- on the eye- what will be the angle subtended by the image on the eyepiece in relaxed eye- In degree

Angular magnification is given by, M=αβ In relaxed eye adjustment, M=f_0f_e=162=8 Given that, α =0.5^∘ ∴ Angular subtended by image, β =Mα =8× 0.5^∘ =4^∘ ...

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Standard XII

Physics

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Question

A telescope consists of two convex lenses of focal length $16 cm$ and $2 cm$ . If the object subtends an angle of ${0.5}^{\circ}$ on the eye, what will be the angle subtended by the image on the eyepiece in relaxed eye? (In degree)

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Solution

Angular magnification is given by,
$M = \frac{α}{β}$

In relaxed eye adjustment,

$M = \frac{f_{0}}{f_{e}} = \frac{16}{2} = 8$

Given that, $α = {0.5}^{\circ}$

$∴$ Angular subtended by image,

$β = M α = 8 \times {0.5}^{\circ} = 4^{\circ}$

Hence, $4$ is the correct answer.

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A telescope consists of two convex lenses of focal length 16 cm and 2 cm. If the object subtends an angle of 0.5∘ on the eye, what will be the angle subtended by the image on the eyepiece in relaxed eye? (In degree)

Angular magnification is given by, M=αβ In relaxed eye adjustment, M=f0fe=162=8 Given that, α=0.5∘ ∴ Angular subtended by image, β=Mα=8×0.5∘=4∘ Hence, 4 is the correct answer.

A telescope consists of two convex lenses of focal length $16 cm$ and $2 cm$ . If the object subtends an angle of ${0.5}^{\circ}$ on the eye, what will be the angle subtended by the image on the eyepiece in relaxed eye? (In degree)

Angular magnification is given by,
$M = \frac{α}{β}$

In relaxed eye adjustment,

$M = \frac{f_{0}}{f_{e}} = \frac{16}{2} = 8$

Given that, $α = {0.5}^{\circ}$

$∴$ Angular subtended by image,

$β = M α = 8 \times {0.5}^{\circ} = 4^{\circ}$

Hence, $4$ is the correct answer.