An object is placed 15cm in front of a concave mirror of focal length 20cm. The image formed is

micoflagos

3 years ago

1/f=1/u+1/v where u = 15cm, f= 20cm
1/v=1/20-1/15=-1/60,
.
. . v= -60cm
when v =negative the image formed is virtual
and in concave mirror, when the image is virtual it is always erect and magnified e.g like your shaving and supermarket mirror

Zoe_ViVi

1 year ago

We all know that a concave mirror can form real or virtual images depending on the object's position relative to the focal point.
Given that the object distance (u) is 15 cm and the focal length (f) is 20 cm, the object is between the focal point and the mirror.

FINDING IMAGE DISTANCE
The mirror formula is 1/f = 1/v + 1/u, where v is the image distance. Given u = -15 cm (object distance is negative for real objects in mirror formulas) and f = -20 cm (focal length is negative for concave mirrors):
1/(-20) = 1/v + 1/(-15)
Find v,
-1/20 = 1/v - 1/15
1/v = 1/15 - 1/20
= (4 - 3) / 60
= 1/60
v = 60 cm
Since v is positive, the image is virtual and behind the mirror.

FINDING THE MAGNIFICATION AND ORIENTATION OF THE IMAGE FORMED
Magnification (m) = -v/u = -60 / -15 = 4
The positive magnification indicates the image is erect, and since |m| > 1, the image is magnified.

Given the image is virtual, erect, and magnified:
The correct answer is D. virtual, erect and magnified.
Thanks 😄

taiwo141009

3 months ago

All image formed by a concave mirror is;
I.Diminished
II.virtual
III.Erect
IV.Magnified