The radius of curvature of a convex mirror used as a rear view mirror in a moving car is 2.0m. A truck is coming from behind it at a distance of 3.5m. Calculate (a) position, and (b) size, of the image relative to the size of the truck. What will be the nature of the image?
Download our app for free and get startedPlay store
R = 2m,$\text{f}=\frac{\text{R}}{2}=1\text{m}$
u = -3.5m We konw that
  1. $\frac{1}{\text{v}}+\frac{1}{\text{u}}=\frac{1}{\text{f}}$
$\Rightarrow\frac{1}{\text{v}}+\frac{1}{(-3.5)}=\frac{1}{1}$
$\Rightarrow\frac{1}{\text{v}}=1+\frac{1}{3.5}=1+\frac{10}{30}=1+\frac{2}{7}=\frac{9}{7}$
$\therefore \text{v}=\frac{7}{9}=0.77\text{m}$
$\text{u}=-2\text{v}=-2\times10=-20\text{cm}$
So, the image is fomed 0.77m in behind the mirror.
  1. Now, $\text{m}=\frac{\text{v}}{\text{u}}=\frac{0.77}{(-3.5)}=\frac{\frac{7}{9}}{3.5}=\frac{1}{4.5}$
AS m is positive, so image formed is virtual and efect.
art

Download our app
and 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

  • 1
    Distinguish between a real and a virtual image of an object. What type of image is formed?
    1. By a plane mirror.
    2. On a cinema screen?
    View Solution
  • 2
    An object of height 4cm is placed at a distance of 15cm in front of a concave lens of power, -10 dioptres. Find the size of the image.
    View Solution
  • 3
    State the type of mirror preferred as,
    1. Rear view mirror in vehicles.
    2. Shaving mirror. Justify your answer giving two reasons in each case.
    View Solution
  • 4
    At what distance from a concave mirror of focal length 10cm should an object 2cm long be placed in order to get an erect image 6cm tall?
    View Solution
  • 5
    Between which two points of concave mirror should an object be placed to obtain a magnification of:
    1. −3
    2. +25
    3. −0.4
    View Solution
  • 6
    Describe with the help of a ray diagram the nature, size and position of the image formed when an object is placed in front of a convex lens between focus and optical centre. State three characteristics of the image formed.
    View Solution
  • 7
    The image of an object place at 60cm in front of a lens is obtained on a screen at a distance of 120cm from it. Find the focal length of the lens. What would be the lens? What would be the height of the image? If the object is 5cm high?
    View Solution
  • 8
    A 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.
    View Solution
  • 9
    An object of 5.0cm size is placed at a distance of 20.0cm from a converging mirror of focal length 15.0cm. At what distance from the mirror should a screen be placed to get the sharp image? Also calculate the size of the image.
    View Solution
  • 10
    We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.
    View Solution