an object 3 centimetre high is placed at a distance of 9 centimetre in the front of concave mirror of focal length 18 cm find the positions and nature of the image formed
Answers
Step-by-step explanation:
the given spherical mirror is a concave mirror and the object is placed 3 cm height from the principal Axis so due to the sign convention it remains positive therefore ho=3cm
and the next part of the question makes understand that the object is placed 9 CM from the concave mirror. due to sign convention the measurement becomes negative therefore object distance, u=- 9 CM
and also the focal length of a concave mirror is to be taken negative due to the sign convention f=-18cm
so here we know the values of height of the object ,object distance and focal length
we know the formula , 1\f=1\v+1\u
1\-18=1\v+1\-9
6-3\-54=1\v
v=-18 cm
the magnification of the image can be found by using the formula - v\u
m,=-(-18)\-9
=18\-9
=-2
As the magnification of the mirror is -2 the image is real and inverted as the magnification number is more than 1 the image is magnified.
Therefore, the size of the image is more
than that of the size of the object
the size of the image is more than that of the size of the objectand given mirror forms a real inverted and magnified image