Question

an object is placed 20cm in front of a concave mirror of focal length 12 cm. find the position and nature of the image. ​

Answer 1

Answer:

$u = - 20cm \\ f = - 12cm \\ \frac{1}{v } = \frac{1}{f} - \frac{1}{u} \\ \frac{1}{v } = \frac{1}{ - 12} - \frac{1}{ - 20 } \\ \frac{1}{v} = \frac{ - 5 + 3}{60 } \\ \frac{1}{v} = \frac{ - 2}{60 } \\ v = \frac{ - 60}{2} = - 30$