The next two problems are concerned with the experimental setup shown in the dia
ID: 1560970 • Letter: T
Question
The next two problems are concerned with the experimental setup shown in the diagram. An upright, 1.0 cm high object is 10.0 cm to the left of the lens and a real image is formed 20.0 cm to the right of the lens. i. The focal length of the lens is closest to: A. +20.0 cm. B. +5.9 cm. C. +7.5cm. D. +15.0 cm. E. +6.7 cm. ii. The orientation and height of the image are closest to: A. inverted and 2.0 cm high. B. inverted and 3.0 cm high. C. upright and 2.0 cm high. D. upright and 3.0 cm high. E. upright and 2.5 cm high.Explanation / Answer
for lens
object distance p = 10 cm
image distance q = 20 cm
from lens equation
1/p + 1/q = 1/f
1/10 + 1/20 = 1/f
focal length f = +6.7 cm <<<<------answer
OPTION (E)
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magnification m = -q/p = -2
magnification m = size of the image/size of the object
size of the image/1 = 2
size of the image = 2
m is negative so the image is inverted
and size is 2cm
inverted and 2 cm high
option (A)