An erect image  3 times the size  of the  object is obtained with a  concave  mirror  of radius of curvature  36  cm. calculate the  position  of  the object

Asked by sisugsgsgsysyhshz | 9th Jun, 2017, 01:42: PM

Expert Answer:

begin mathsize 12px style For space concave space mirror colon
straight m equals 3 semicolon space straight f equals straight R over 2 equals negative 18 space cm left parenthesis negative space because space it space is space straight a space concave space mirror right parenthesis
From space the space formula space of space magnification colon
straight m equals negative straight v over straight u
therefore straight v equals negative 3 straight u
From space mirror space equation colon
1 over straight v plus 1 over straight u equals 1 over straight f
therefore fraction numerator 1 over denominator negative 3 straight u end fraction plus 1 over straight u equals fraction numerator 1 over denominator negative 18 end fraction
fraction numerator negative 1 plus 3 over denominator 3 straight u end fraction equals fraction numerator negative 1 over denominator 18 end fraction
therefore fraction numerator 2 over denominator 3 straight u end fraction equals fraction numerator negative 1 over denominator 18 end fraction
therefore 3 straight u equals negative 36
therefore straight u equals negative 12 space cm end style

Answered by Romal Bhansali | 9th Jun, 2017, 03:40: PM