image of a candle flame placed at a distance of 45 cm from a spherical lens is formed on a screen placed at a distance of 90 cm from the lens. Identify the type of lens and calculate its focal length. If the height of the flame is 2 cm, find the height of its image. Ii) Anobject 5 cm in length is placed at the distance of 20 cm in front a convex mirror of radius of curvature 30 cm. Find the position of the image, its nature and size?
Answers
Answered by
0
Explanation:
plzzz make me brainliest answer
Attachments:
Answered by
0
Answer:
According to the question;
Object distance, u=−45 cm
Image distance, v=90 cm
By lens formula,
v/1 − u/1 = f/1
⇒ 1/90 cm− 1/−45 cm = 1/f
⇒ 1/f = 1/90 cm + 1/45 cm
⇒ 1/f =1+2/ 90 cm = 3/90 cm
⇒ 1/f = 1/30 cm
⇒f=30 cm
Since f=30 cm which is positive, hence it is a convex lens of focal length 30cm.
Now,
Height of Flame, h 1 =2 cm
Magnification, m= h 2/h1= v/u
Putting values of v and u.
h 2 =−2
⇒h 2=−2×2 cm=−4 cm
Height of image is 4 cm and the negative sign means image is inverted.
Similar questions