Write the expression to calculate:
1) Focal length of a convex lens.
2) Magnification.
3) Magnifying power of a lens.
4) Height of an image.
Answers
Answer:
1.Note the value of u and v. You can calculate the focal length (F) of combination of lenses using the formula F = uv/(u+v). The focal length of convex lens (f1) is shown inside the simulator window. You can calculate the focal length of the concave lens using the formula f2 = (f1F/(f1-F).
2.Magnification. The magnification produced by a lens is defined as ratio of the height of the image to the height of the object. It is denoted by “\begin{align*}m\end{align*}”. The magnification produced by a lens is equal to the ratio of image distance to the object distance
3.If you know the distance of the object you're magnifying from the lens and the focal length of the lens, finding the distance of the image is easy with the lens equation. The lens equation is 1/f = 1/do + 1/di, where f = the focal length of the lens. In our example problem, we can use the lens equation to find di.
4.You then multiply the height of the object by the magnification: If m>1, the height of the image will be how ever many times larger the magnification is. if m<1, the height of the image will be how every many times smaller the magnification is. If the magnification is negative, then the image is inverted.