00:01
Here it is given then a candle is placed 49 .0 cm in front of a spherical concave mirror and the radius of curvature of the mirror is given as 70 .0 the relation between radius of curvature and focal length is are equal to 2f.
00:27
So the focal length of the concave mirror can be returned as r by 2.
00:34
So it is 70 .0 cm divided by 2 and the focal length is 35 .0 centimeter.
00:46
Here the sign convention is used and all the distances are measured from the mirror.
00:55
For positive values that is measured along the direction of incident ray and for the distance measured against the incident ray as considered as negative values so the object distance can be written as minus 49 .0 centimeter and the focal length will be minus 35 point 0 cm and the focal length will be minus 35 point 0 cm by applying the sign convention.
01:35
The mirror equation can be written as 1 by f equal to 1 by v plus 1 by u.
01:44
Here v is the image distance.
01:47
So the image distance that is 1 by v can be written as 1 by f minus 1 by u.
01:57
We can substitute the values to find the image distance so it will become a 1xv equal to 1 pi minus 35 .0 cm minus 1 pi minus 49 .0 centimeter.
02:15
By calculation we will get it is 1 pi v equal to minus 2 by 245 cm.
02:25
By taking the reciprocal the image distance that is p will be minus 1.
02:33
22 .5 cm.
02:38
Part a is asked to find the image distance...