Answer:
Focal Length = f = - 8/3 m
Explanation:
Considering the lens is concave and for concave lens image distance and focal length are negative.
Image distance = q = -2 m
Object distance = p = 8 m
Focal Length = f = ?
Using concave lens formula,
1/f = 1/p + 1/q ………… (i)
By putting values in equation (i)
1/f = 1/8 -1/2
1/f = 1-4/8
f = -8/3 m
