Please show work, thanks :) A diverging lens has a focal length of -10.00 cm. (a
ID: 1631251 • Letter: P
Question
Please show work, thanks :)
A diverging lens has a focal length of -10.00 cm.
(a) What are the image distances q for objects placed at the distances p from the lens which are tabulated below? In each case, calculate the magnification m, describe the image as real or virtual, upright or inverted, and enlarged or diminished in size.
(b) If the object is 4.00 cm high, what is the height of the image for the object distances of 5.00 cm and 20.0 cm?
Explanation / Answer
We know that the diverging lens can produce always
the image is VIRTUAL , UPRIGHT , DIMINISHED IMAGES
Given focal length is f = -10 cm, object distance p , image distance q, magnification is m = -q/p
the relation between p,q,f is , 1/f = 1/p +1/q==> 1/q = 1/f-1/p
iamge distance
for p=5 cm, 1/q = -1/10 -1/5,q = -3.33 cm ;
for p=10cm, 1/q = -1/10 -1/10 = -5 cm;
for p=14 cm, 1/q = -1/10 -1/14 = -5.833 cm;
for p = 16 cm, 1/q = -1/10 -1/16 = -6.154 cm;
for p = 20 cm, 1/q = -1/10 -1/20 = -6.66 cm;
Magnification m= -q/p = -(-3.33)/5 = 0.666 ;m = -(-5)/10= 0.5;m = -(-5.833)/14= 0.41664; m= -(-6.154)/16= 0.384625;m = -(-6.66)/20 = 0.333
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In all the cases the image is virtual image and upright image
In all the cases the image is diminished..
b)
p = 5c, , y = 4 cm and f = -10 cm
1/q = 1/f - 1/p = -1/10 - 1/5==> q = -3.33 cm
for p=10 cm , 1/q = -1/10 -1/10 = -5 cm
now height of the image is m= -q/p= y'/y ==>y' = -q*y/p
for p=5 cm , y' = -(-3.33)*4/5 cm = 2.664 cm
for p=10 cm , y' = -(-5)*4/10 cm = 2 cm