An object is placed 20cm from a concave mirror of focal length 15cm. Calculate the linear magnification of the image formed
A
0.5
B
1.5
C
2.0
D
3.0
Verified Correct Answer: D.
Physical Principles & Numerical Solution
\(\frac{1}{U} + \frac{1}{V} = \frac{1}{F}\)
\(\frac{1}{V} = \frac{1}{F} - \frac{1}{U}\)
\(\frac{1}{V} = \frac{1}{15} - \frac{1}{20}\)
\(\frac{1}{V} = \frac{\text{4 - 3}}{60}\)
\(\frac{1}{V} = \frac{1}{60}\)
V = 60cm
M = \(\frac{V}{U} = \frac{60}{20}\)
M = 3.0cm
Source: Myschool Past Questions Archive (Record #45523)