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STD 12 - 9. Ray optics abd optical instruments — NEET STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 12 - 9. Ray optics abd optical instruments4 Marks
MCQ
A plane mirror is placed along the $x-$ axis facing negative $y-$ axis. The mirror is fixed. A point object is moving with velocity $3\hat i + 4\hat j$ in front of plane mirror. The relative velocity of image with respect of its object
  • ✓
    $-8j$
  • B
    $8j$
  • C
    $3i -4j$
  • D
    $-6i$
✓

Answer

Correct option: A.
$-8j$
a
${\overrightarrow v _{obj}} = 3\hat i + 4\hat j,\quad {\overrightarrow v _{im}} = 3\hat i - 4\hat j$

${\overrightarrow v _{rel}} = {\overrightarrow v _{in}} - {\overrightarrow v _{obj}} = 3\hat i - 4\hat j - 3\hat i - 4\hat j =  - 8\hat j$

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