Answers

2015-05-09T17:17:07+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Size of object, h = 7.5cm
radius of curvature of convex mirror, R = +25cm
focal length, f = R/2 = 25/2 cm
object distance, u = -40cm
image distance = v

we know that
 \frac{1}{v} + \frac{1}{u}= \frac{1}{f} \\ \\ \Rightarrow  \frac{1}{v}= \frac{1}{f} -  \frac{1}{u}\\ \\ \Rightarrow  \frac{1}{v}= \frac{1}{25/2} -  \frac{1}{40}\\ \\ \Rightarrow  \frac{1}{v}= \frac{2}{25} -  \frac{1}{40}\\ \\ \Rightarrow  \frac{1}{v}= \frac{16-5}{200}\\ \\ \Rightarrow  \frac{1}{v}= \frac{11}{200}\\ \\ \Rightarrow  v= \frac{200}{11}cm

magnification =  \frac{h'}{h} =- \frac{v}{u}
h' = height of image

\frac{h'}{h} =- \frac{v}{u}\\ \\ h' = -h \times \frac{v}{u}=-7.5 \times \frac{200}{11 \times (-40)}= \frac{75}{22}\ cm=3.41cm

Size of image is 3.41cm.
0