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Units, Dimensions and Measurement — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsUnits, Dimensions and Measurement1 Mark
Question
Assertion : Parallex method cannot be used for measuring distances of stars more than 100 light years away.
Reason : Because parallex angle reduces so much that it cannot be measured accurately.
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Answer

(a) As the distance of star increases, the parallax angle decreases, and great degreeofaccuracy is required for its measurement. Keeping in view the practical limitation imeasuring the parallax angle, the maximum distance of a star we can measure is limited to100 light year.

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