A concave mirror has a focal length of 4cm and an object 2cm tall is placed 9cm away from it. Find the nature, position and size of the image formed.
Download our app for free and get started
$h_1=2 cm, u =-9 cm, f =-4 cm$ We know that$\frac{1}{\text{v}}+\frac{1}{\text{u}}=\frac{1}{\text{f}}$
$\frac{1}{\text{v}}=\frac{1}{\text{f}}-\frac{1}{\text{u}}=\frac{1}{(-4)}-\frac{1}{(-9)}$
$\frac{1}{4}+\frac{1}{9}=\frac{-9+4}{36}=\frac{5}{36}$
$\text{v}=-7.2\text{cm}$
The image is formed at a distance of 7.2cm in front of the mirror. Again $\text{m}=-\frac{\text{v}}{\text{u}}=-\frac{(-7.2)}{-9}=-0.8$$\Rightarrow\text{m}=\frac{\text{h}_2}{\text{h}_1}=-0.8$ $\Rightarrow\frac{\text{h}_2}{2}=\text{h}_2=-1.6\text{cm}$$$$$
So, Image is 1.6cm in size, real and inverted.
$\frac{1}{\text{v}}=\frac{1}{\text{f}}-\frac{1}{\text{u}}=\frac{1}{(-4)}-\frac{1}{(-9)}$
$\frac{1}{4}+\frac{1}{9}=\frac{-9+4}{36}=\frac{5}{36}$
$\text{v}=-7.2\text{cm}$
The image is formed at a distance of 7.2cm in front of the mirror. Again $\text{m}=-\frac{\text{v}}{\text{u}}=-\frac{(-7.2)}{-9}=-0.8$$\Rightarrow\text{m}=\frac{\text{h}_2}{\text{h}_1}=-0.8$ $\Rightarrow\frac{\text{h}_2}{2}=\text{h}_2=-1.6\text{cm}$$$$$
So, Image is 1.6cm in size, real and inverted.
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 2.0cm tall object is placed 40 cm from a diverging lens of focal length 15cm. Find the position and size of the image.
- 2View SolutionAn object 4 cm in height, is placed at 15 cm in front of a concave mirror of focal length 10 cm. At what distance from the mirror should a screen be placed to obtain a sharp image of the object. Calculate the height of the image.
- 3View SolutionA man holds a spherical shaving mirror of radius of curvature 60cm, and focal length 30cm, at a distance of 15cm, from his nose. Find the position of image, and calculate the magnification.
- 4View SolutionUnder what condition in an arrangement of two plane mirrors, incident ray and reflected ray will always be parallel to each other, whatever may be angle of incidence. Show the same with the help of diagram.
- 5View SolutionHow far should an object be placed from a convex lens of focal length 20cm to obtain its image at a distance of 30cm from the lens? What will be the height of the image, if the objects is 6cm tall?
- 6View SolutionAn object of size 7.0cm is placed at a distance of 27cm in front of concave mirror of focal length 18cm. At what distance from the mirror should a screen be placed so that a sharply focused image can be obtained? Find the size and the nature of the image.
- 7View SolutionExplain with the help of a labelled ray diagram, why a pencil partly immersed in water appears to be bent at the water surface. State whether the bending of pencil will increase or decrease if water is replaced by another liquid which is optically more dense than water. Give reason for your answer.
- 8View SolutionWhat is lateral inversion? Explain by giving a suitable example.
- 9View SolutionGive the position, size and nature of image formed by a concave lens when the object is placed:
- Anywhere between optical centre and infinity.
- At infinit.
- 10View SolutionA converging mirror forms a real image of height 4cm of an object of height 1cm placed 20cm away from the mirror:
- Calculate the image distance.
- What is the focal length of the mirror?