JAMB - Physics (2008 - No. 23)
An object of heights 5 cm is placed at 20 cm from a concave mirror of focal length 10 cm. the image height is?
20 cm
15 cm
10 cm
5 cm
توضیح
(1)/V + (1)/U = (1)/f
(1)/V + (1)/20 = (1)/10
(1)/V = (1)/10 - (1)/20 = (2 -1)/20 = (1)/20
∴ V = 20 cm
mag = (image height)/object height = (v)/u
(X)/5 = (20)/50
X = 5 cm
(1)/V + (1)/20 = (1)/10
(1)/V = (1)/10 - (1)/20 = (2 -1)/20 = (1)/20
∴ V = 20 cm
mag = (image height)/object height = (v)/u
(X)/5 = (20)/50
X = 5 cm