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A student uses a convex lens to determine the width of a slit. For this he fixes the positions of the object and the screen and moves the lens to get a real image on the screen. The images of the slit width are found to be 2.1 cm and 0.48 cm wide respectively when the lens is moved through 15 cm . Therefore, the slit width and the focal length of the lens respectively, are

Options

  1. A1 ~cm , 9.3 ~cm
  2. B1 ~cm , 10.5 ~cm
  3. C2 ~cm , 12.8 ~cm
  4. D2 ~cm , 15.2 ~cm

Correct answer

A. 1 ~cm , 9.3 ~cm

Step-by-step solution

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