1
Question
An object 4 cm in size, is placed 25 cm in front of a concave mirror of focal length 15 cm. At what
distance from the mirror should a screen be placed in order to obtain a sharp image ? Find the nature
and the size of the image.
distance from the mirror should a screen be placed in order to obtain a sharp image ? Find the nature
and the size of the image.
Open in App
Solution
Dear Student,
object distance, u=−25 cmfocal length, f=−15 cmheight of object, h=4 cm1v+1u=1f1v+1(−25)=1(−15)1v=125−1151v=3−575image distance, v=−752=−37.5 cmmagnification, m=h'h=−vuh'4=−(−37.5)(−25)height of image, h'=−15025=−6 cmm=h'hm=−64=−1.25So, the image is real and inverted as m is negative and magnified as h'>h.
Regards
object distance, u=−25 cmfocal length, f=−15 cmheight of object, h=4 cm1v+1u=1f1v+1(−25)=1(−15)1v=125−1151v=3−575image distance, v=−752=−37.5 cmmagnification, m=h'h=−vuh'4=−(−37.5)(−25)height of image, h'=−15025=−6 cmm=h'hm=−64=−1.25So, the image is real and inverted as m is negative and magnified as h'>h.
Regards
Suggest Corrections
14
Similar questions