an object of height 7 cm placed at distance of 30 cm from a convex lens produces at a distance of 45 cm. find out centre of curvature, magnification and height of image.
An object 5.0cm in length is placed at a distance of 20cm in front of a convex mirror of radius of curvature 30cm. Find the position of the image, its nature, and its size.
Medium
Solution
verified
Verified by Toppr
Given: u=−20 cm
f=R/2=15 cm
Size of image, h=5 cm
Let size of image be h
′
From mirror formula,
u
1
+
v
1
=
f
1
−20
1
+
v
1
=
15
1
v=
7
60
=8.57 cm
The image is formed 8.57cm behind the mirror. It is virtual and erect.
Answers & Comments
Answer:
search-icon-header
Search for questions & chapters
search-icon-image
Class 12
>>Physics
>>Ray Optics and Optical Instruments
>>Problems on Mirror and Magnification Formula
>>An object 5.0 cm in length is placed at
Question
Bookmark
An object 5.0cm in length is placed at a distance of 20cm in front of a convex mirror of radius of curvature 30cm. Find the position of the image, its nature, and its size.
Medium
Solution
verified
Verified by Toppr
Given: u=−20 cm
f=R/2=15 cm
Size of image, h=5 cm
Let size of image be h
′
From mirror formula,
u
1
+
v
1
=
f
1
−20
1
+
v
1
=
15
1
v=
7
60
=8.57 cm
The image is formed 8.57cm behind the mirror. It is virtual and erect.
Magnification, m=−v/u=8.57/20=0.428
Also, m=h
′
/h=h
′
/5
From above, h
′
/5=0.428
h
′
=2.14 cm
Explanation:
Hope it help you !