Q148 / 200 · Manipal (MET) 2011 · Physics

While viewing a distant object with a telescope suddenly a housefly sits on objective lens. The correct statement is that

A
housefly will be seen enlarged in image
B
housefly will be seen reduced in image
Correct answer
C
intensity of image will be decreased
D
intensity of image will be increased

Solution

If housefly sits on objective lens, then the intensity of image will decrease, because some of light rays will be stopped by housefly but housefly will not be seen.

Hence, the correct answer is option: 'C'.

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