A spherical mirror produces an image of magnification -1.0 on a screen placed at a distance of 30 cm from the pole of the mirror.
- Write the type of mirror in this case.
- What is the focal length of the mirror?
- What is the nature of the image formed?
- Draw the ray diagram to show the image formation in this case.
CBSE DELHI - SET 3 2014
Download our app for free and get started
- Spherical mirror.
- Magnification, m = -1
- image is formed on the screen.
- image distance, v = -30 cm (-ve sign for real image)
- Concave mirror.
- $f = ?$
| $\frac{-v}{u}$ | $\Rightarrow$ | $\frac{-(-30)}{u} = -1$ |
| $\Rightarrow 30 = -u$ | $\therefore$ | $u = -30 \text{ cm}$ |
| $\frac{1}{f} = \frac{1}{v} + \frac{1}{u}$ | $\Rightarrow$ | $\frac{1}{f} = \frac{1}{-30} + \frac{1}{-30}$ |
| $\frac{1}{f} = -\frac{1}{30} - \frac{1}{30} = \frac{-2}{30} = \frac{-1}{15}$ | $\therefore$ | $f = -15 \text{ cm}$ |
- Image is real, inverted and same size of the object.
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1View SolutionA 4 cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 24 cm. The distance of the object from the lens is 16 cm. Find the position, size and nature of the image formed, using the lens formula.
- 2View SolutionAn object is kept at a distance of 100cm from each of the above lenses. Calculate the (i) image distance and (ii) magnification in each of the two cases.
- 3View SolutionAn object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image.
- 4View SolutionWith the help of a labelled diagram, explain why a tank full of water appears less deep than it actually is.
- 5View SolutionState where an object must be placed so that the image formed by a concave mirror is:
- Erect and virtual.
- At infinity.
- The same size as the object.
- 6View SolutionDefine power of a lens. What is its unit? One student uses a lens of focal length 50cm and another of -50cm. What is the nature of the lens and its power used by each of them?
- 7View SolutionWhat is lateral inversion? Explain by giving a suitable example.
- 8View SolutionFor which position of the object does a convex lens form a virtual and erect image? Explain with the help of a ray diagram.
- 9View SolutionA convex lens produces an inverted image magnified three times of an object placed at a distance of 15cm from it. Calculate focal length of the lens.
- 10Size of image of an object by a mirror having a focal length of 20cm is observed to be reduced to $\frac{1}{3}\text{rd}$ of its size. At what distance the object has been placed from the mirror? What is the nature of the image and the mirror?View Solution