A concave mirror of focal length ‘f’ produces an image ‘n’ times the size of the object. If the image is real, then the distance’d’ of the object from the mirror is
A) \(\cfrac{(n+1)f}n\)
B) (n + 1) f
C) (n – 1) f
D) \(\cfrac{(n-1)f}n\)
1 Answers
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Let \( \vec{a}, \vec{b}, \vec{c} \) be unit vectors such that \( \vec{a}+\vec{b}+\vec{c}=\overrightarrow{0} \). Which one of the following is correct ? [IIT-2007] (a) \( \vec{a} \times \vec{b}=\vec{b} \times \vec{c}=\vec{c} \times \vec{a}=\overrightarrow{0} \) (b) \( \overrightarrow{ a } \times \overrightarrow{ b }=\overrightarrow{ b } \times \overrightarrow{ c }=\overrightarrow{ c } \times \overrightarrow{ a } \neq \overrightarrow{0} \) (c) \( \overrightarrow{ a } \times \overrightarrow{ b }=\overrightarrow{ b } \times \overrightarrow{ c }=\overrightarrow{ a } \times \overrightarrow{ c } \neq \overrightarrow{0} \) (d) \( \vec{a} \times \vec{b}, \vec{b} \times \vec{c}, \vec{c} \times \vec{a} \) are mutually \( \perp \)
Given that \(\vec a, \vec b\) and \(\vec c\)are unit vectors. i.e., |\(\vec a\)| = |\(\vec b\)| = |\(\vec c\)| = 1 And \(\vec a\) + \(\vec b\) + \(\vec c\) = \(\vec 0\) Then \((\vec a+\vec b+\vec c).(\vec a+\vec b+\vec c)=\vec 0.\vec...
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The real image formed by a concave mirror is larger than the object when the object is ……………..
C) between focus and centre of curvature
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Correct option is C) 20 cm
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D) The mirror and the screen
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Correct option is C) – 54 cm
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Correct option is C) – 21 cm
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Correct option is A) 12 cm
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