Question

Pls. hep me answer these questions and show solution Thanks

1.You have a converging (convex) lens and a diverging (concave) lens and the magnitude of the focal length of each lens is 44.4 cm.Determine how far from the lens you should locate the screen in order to produce an image of the light bulb that is magnified by a factor of 1.55. (Answer in m)

2.A lens is needed to provide an image with a height of −6.80 cm. The object is a person who is 1.60 m tall standing 7.1 m away from the lens.  What is the focal length of the lens in cm?

Answer 1

object distance from lens = u Image distance from leng = v height of image = he height of of object focal lengtha f magnification=m. =h 0 f = 44.4 cm mov u = 1.55 & v= l. 554 & ua (rss) lans formula ㅗ ! u f 1.55 D 11 ol- V V 0.55 -F (0.55) >> f V=-44.4cm Co-ss) v=-24.42cme 0-24m we have to fut a 0.2um lens 1 away from the the screen 2) after using standard sign convention u=-7-1m- -7 10cm his -6.80cm hos 1.6omma 160cm m= han ul hi J = -7100mp song * va -710cm/-6.80cm 160cm *V= 30-175cm lens formula! u 나 ☆ f ( u 7100 30.1756m 30.175cm 710cm 710 +30.175 - 1 f 30.1758 7loom > f = 28.94cm D f= 0.28am 7 focal length Scanned with CamScanner