WAEC - Physics (1996 - No. 33)
A converging lens of focal length 5cm forms a virtual image which is 10cm from the lens. How far from the lens is the object?
2.0cm
3.3cm
5.0cm
10.0cm
15.0cm
Explanation
\(f = \frac{uv}{u+v}\)
\(5 = \frac{-10u}{-10+u}\)
\(50 + 5u = -10u\)
\(50 = -10u - 5u\)
\(u = \frac{50}{-15}\)
u= -3.3cm
Comments (0)
