Question

Oblicz ile:

a)wynosi y skoro x=9 [cm], a 1/f= 0,102 [1/m]

b) wynosi y skoro x=20 [cm], a 1/f= 0,101 [1/m]

Answer 1

a)

dane:

x = 9 cm = 0,09 m

Z = 1/f = 0,102/m

szukane:

y = ?

 

f = 1/Z

f = 1/0,102

f = 9,8 m

 

Z równania soczewki:

1/f = 1/x + 1/y

1/y = 1/f - 1/x

1/y = (x-f)/xf

y = xf/(x-f) = 0,09m*9,8m/(0,09m-9,8m) = 0,882m²/(-9,71m)

y = -0,09 m

y = -9 cm

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b)

dane:

x = 20 cm = 0,2 m

Z = 1/f = 0,101/m

szukane:

y = ?

 

f = 1/Z

f = 1/0,101

f = 9,9 m

 

y = xf/(x-f) = 0,2m*9,9m/(0,2m-9,9m = 1,98m²/(-9,7m)

y = -0,2 m

y = -20 cm

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