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A telescope has an objective lens of focal length 150 cm and an eyepiece of focal length 5 cm. If a 50 m tall tower at a distance of 1 km is observed through this telescope in normal setting, the angle formed by the image of the tower is theta, then theta is close to : |
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Answer» `1^(@)` Let the angle formed by tower be `ALPHA` `tan alpha=(50M)/(1km)=(50)/(1000)=(1)/(20)` `alpha=(2.86)^(@)` Let the angle formed by image be `beta` `tan beta=m tan alpha` `=30xx(1)/(20)` `tan beta=1.5` `beta=56.31~~57^(@)` Which is closest to `60^(@)`. |
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