Question #fadc9

1 Answer
Jun 22, 2016

#"a :Object distance is 20 cm"#
#"b :Mirror is convex"#

Explanation:

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#"given:"#

#f:"focus :r:radius ;g:length of image ; c:length of object"#
#u="distance between object and mirror"#
#u'="distance between image and mirror"#
#r=60" cm ; f="60/2="30 cm"#

#g/c=(u')/u" ; "6/10=(u')/u" ; "u'=(6u)/10#

#-1/f=1/u-1/(u')" equation for convex mirrors"#

#-1/30=1/u-1/((6u)/10)#

#-1/30=1/u-10/(6u)#

#-1/30=(6-10)/(6u)#

#-1/30=-4/(6u)#

#120=6u#

#u=20" cm"#