Question
Part A What are the focal length of the lens? Express your answer using two significant figures. Part B What are the lateral magnification of the image? Express your answer using two significant figures. M = ______ Part A Express your answer using two significant figures. _______ Part B What is the orientation of the image of the tree on the retina? upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted upright inverted =_______
Explanation / Answer
1.Given Object distance , do = 32 cm Image distance , di = 16 cm A) Focal length of the lens 1/ f = 1/do + 1/di = 1/ 32 cm + 1/ 16 cm f = 10.67 cm B) Magnification, M = - do / di = - 32cm / 16cm M = - 2 Since M is negative , the image is inverted 2. Focal length , f = 1.7 cm Height of the object , ho = 2.4 m Object distance , do = 20 m A) The image distance is 1/di = 1/f - 1/do = 1/1.7cm - 1/(20*10^3 cm) di = 1.70 cm Magnification, M = - di / do = hi / ho - 1.70 cm / 20 *10^3 cm = hi / 2.4*10^3 m hi =- 2.04 mm B) Here , image height is negative so the image is inverted on the retina