Advertisements
Advertisements
Question
A mobile phone lies along the principal axis of a concave mirror. Show, with the help of a suitable diagram, the formation of its image. Explain why magnification is not uniform.
Solution
The image of the mobile phone formed by the concave mirror is shown in the above figure.
The part of the mobile phone that is at C will form an image of the same size only at C.
In the figure, we can see that B'C = BC. The part of the mobile phone that lies between C and F will form enlarged image beyond C as shown in the figure. It can be observed that the magnification of each part of the mobile phone cannot be uniform on account of different locations. That is why the image formed is not uniform.
APPEARS IN
RELATED QUESTIONS
Suppose the lower half of the concave mirror's reflecting surface is covered with an opaque material. What effect this will have on the image of the object? Explain
A convex lens of focal length 20 cm is placed coaxially with a concave mirror of focal length 10 cm at a distance of 50 cm apart from each other. A beam of light coming parallel to the principal axis is incident on the convex lens. Find the position of the final image formed by this combination. Draw the ray diagram showing the formation of the image
Draw a ray diagram to show image formation when the concave mirror produces a real, inverted and magnified image of the object.
A convex lens of focal length 20 cm is placed coaxially in contact with a concave lens of focal length 25 cm. Determine the power of the combination. Will the system be converging or diverging in nature?
A convex lens of focal length f1 is kept in contact with a concave lens of focal length f2. Find the focal length of the combination.
Use Huygens’ geometrical construction to show the behavior of a plane wavefront.
(i) Passing through a biconvex lens;
(ii) Reflecting by a concave mirror
Find the diameter of the image of the moon formed by a spherical concave mirror of focal length 7.6 m. The diameter of the moon is 3450 km and the distance between the earth and the moon is 3.8 × 105 km.
A concave mirror of radius R is kept on a horizontal table (See figure). Water (refractive index = μ) is poured into it up to a height h. Where should an object be placed so that its image is formed on itself?
A gun of mass M fires a bullet of mass m with a horizontal speed V. The gun is fitted with a concave mirror of focal length f facing towards the receding bullet. Find the speed of separation of the bullet and the image just after the gun was fired.
A mass m = 50 g is dropped on a vertical spring of spring constant 500 N m−1 from a height h = 10 cm as shown in figure. The mass sticks to the spring and executes simple harmonic oscillations after that. A concave mirror of focal length 12 cm facing the mass is fixed with its principal axis coinciding with the line of motion of the mass, its pole being at a distance of 30 cm from the free end of the spring. Find the length in which the image of the mass oscillates.
