An object 3cm high is kept in front of a concave mirror of focal length 30cm .Where should the screen be placed to form a two times magnified sharp image on the screen?

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$F o r i m a g e t o b e m a g n i f i e d a n d f o r r e a l i m a g e o b j e c t s h o u l d b e p l a c e d b e t w e e n f o c u s a n d c e n t r e o f c u r v e t u r e f o r m u l a o f m a g n i f i c a t i o n m = \frac{f}{f - u} - 2 = \frac{- 30}{- 30 - (- u)} - 2 = \frac{- 30}{u - 30} - 2 u + 60 = - 30 2 u = 90 u = \frac{90}{2} = 45 c m R e g a r d s$

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An object 3cm high is kept in front of a concave mirror of focal length 30cm .Where should the screen be placed to form a two times magnified sharp image on the screen?

Dear student For image to be magnified and for real image object should be placed between focus and centre of curvetureformula of magnificationm=ff-u-2=-30-30-(-u)-2=-30u-30-2u+60=-302u=90u=902=45cmRegards