Knowee
Questions
Features
Study Tools

An object is placed 12 cm in front of a lens with a focal length of 8.0 cm.(i) (2 marks)Calculate the image distance.(ii) (2 marks)Sketch a ray diagram of the image, and lens, showing at least the three principal rays. You may include more relevant rays if you wish.

Question

An object is placed 12 cm in front of a lens with a focal length of 8.0 cm.(i) (2 marks)Calculate the image distance.(ii) (2 marks)Sketch a ray diagram of the image, and lens, showing at least the three principal rays. You may include more relevant rays if you wish.

🧐 Not the exact question you are looking for?Go ask a question

Solution

(i) To calculate the image distance, we can use the lens formula which is 1/f = 1/v - 1/u. Here, f is the focal length, v is the image distance, and u is the object distance.

Given: f = 8.0 cm (focal length) u = -12 cm (object distance is negative as it is on the same side as light is coming from)

We can substitute these values into the lens formula:

1/f = 1/v - 1/u 1/8 = 1/v - 1/(-12) 1/8 = 1/v + 1/12

To solve for v, we first get a common denominator and combine the fractions:

3/24 = 1/v + 2/24 1/v = 3/24 - 2/24 1/v = 1/24

Finally, we take the reciprocal of both sides to solve for v:

v = 24 cm

So, the image distance is 24 cm.

(ii) As a text-based AI, I'm unable to sketch a ray diagram. However, I can explain how to do it:

  1. Draw a straight horizontal line to represent the principal axis.
  2. Draw a vertical line in the middle of the principal axis to represent the lens.
  3. Mark the focal point (F) on both sides of the lens at 8 cm from the lens.
  4. Draw an object as an upright arrow on the left side of the lens at 12 cm from the lens.
  5. Draw three principal rays:
    • Ray 1: Draw a straight line from the top of the object passing through the lens. This ray goes straight through the lens without bending.
    • Ray 2: Draw a line from the top of the object through the focal point on the right side of the lens. After passing through the lens, this ray will go parallel to the principal axis.
    • Ray 3: Draw a line from the top of the object parallel to the principal axis. After passing through the lens, this ray will go

This problem has been solved

Similar Questions

An object placed in front of a lens, forms a virtual image whose magnifications is 0.5. The focal length of the lens is 30cm. Calculate the object distance.(with sign)

An object is placed 65.7 cm from a converging lens that has a focal length of 24.6 cm. Determine the image distance. Enter a – answer if appropriate.Image DistancecmInfoAttempts: 0/∞SubmitDetermine the magnification of this image. Enter a – answer if appropriate.

An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens upto two places of decimal.

An object is placed at a distance of 20 cm from a convex lens of focal length 10 cm. The image is formed on the other side of the lens at a distance20 cm10 cm40 cm30 cm

Same size of image is formed by a convex lens of focal length 20 cm . The distance betweenthe object and image is(a) 0 cm (b) 20 cm(c) 40 cm (d) 80 cm1

1/3

Upgrade your grade with Knowee

Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.