Geometrical Optics. Find the correct option(s)?

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2 Answers
Apr 5, 2017

#"option C"#

Explanation:

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#" If there was not the convex mirror, the image of point A (-50.0) would be at point D (75,0)."#

#f:"focus"#

#u:"distance object and mirror or lens"#

#u':"distance image and mirror or lens"#

#1/f=1/u+1/(u')#

#1/30=1/50+1/(u')#

#1/(u')=1/30-1/50#

#1/(u')=(5-3)/150#

#1/(u')=2/150#

#u'=75#

#"The image at point D (75,0) behaves like a virtual object for the convex mirror."#

#"If the axes of the thin-edge lens and the convex mirror coincided, the image of point D (75,0) would be at O (0,0). "#

#-1/f=-1/u+1/(u')#

#-1/50=-1/25+1/(u')#

#1/(u')=-1/50+1/25#

#1/u'=(-1+2)/50#

#u'=50#

#" The Point O (0,0) also rotates 30 degrees when the spherical mirror rotates 30 degrees."#

#" We should rotate the point O(0,0) as 30 degrees."#

#Delta x=50*cos 30=(50*sqrt3)/2=25sqrt 3#

#Delta y=50*sin 30=50*0.5=25#

#"Coordinates of image of A(-50,0) is " (50-25sqrt 3,25)#

Apr 6, 2017

#"I have drawn again. The drawing have been scaled. "#
#"The answer is on the drawing."#

Explanation:

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#"The answer is on the drawing."#