JAMB - Physics (1987 - No. 28)
An object 3.0cm high is placed 60.0cm from a converging lens whose focal length is 20.0cm. Calculate the size of the image formed
0.5cm
1.5cm
2.0cm
6.0cm
Forklaring
F = \(\frac{UV}{U + V}\)
20 = \(\frac{60 \times V}{60 + V}\)
V = 30cm
similarly, \(\frac{U}{V}\) = \(\frac{\text{height of object}}{\text{height of image}}\)
\(\frac{60}{30}\) = \(\frac{3}{h}\)
h = 1.5cm
20 = \(\frac{60 \times V}{60 + V}\)
V = 30cm
similarly, \(\frac{U}{V}\) = \(\frac{\text{height of object}}{\text{height of image}}\)
\(\frac{60}{30}\) = \(\frac{3}{h}\)
h = 1.5cm