Advertisements
Advertisements
प्रश्न
Write the formula for a lens connecting image distance (v), object distance (u) and the focal length (f). How does the lens formula differ from the mirror formula?
Advertisements
उत्तर
Lens formula is:
`1/v-1/u=1/f`
Now, the mirror formula is given by:
`1/v+1/u=1/f`
In both the formulas,
u = Object distance
v = Image distance
f = Focal length
In mirror formula, positive sign is present between the reciprocals of image distance and object distance .
In lens formula, negative sign is present between the reciprocals of image distance and object distance.
APPEARS IN
संबंधित प्रश्न
A student used a device (X) to obtain/focus the image of a well illuminated distant building on a screen (S) as shown below in the diagram. Select the correct statement about the device (X).
Define Radius of curvature of the spherical mirror
What do you mean by the term dispersion?
Explain the following terms :
Pole, Centre of curvature, Radius of curvature, Principal axis. Show them on separate diagrams for each of the concave and convex mirrors.
The diagram below in Figure, shows a convex mirror. C is its centre of curvature and F is its focus. (i) Draw two rays from A and hence locate the position of image of object OA. Label the image IB. (ii) State three characteristics of the image.
Name the kind of mirror used to obtain:
A real and diminished image.
Upto what maximum distance from a concave mirror, the image can be obtained? What will be the location of object for it?
The erect image formed by a concave mirror is of size double the size of object. How are u and v related?
A straight stick partly dipped in water obliquely appears to be bent at the surface of the water.
Define the following term:
convex mirror
What is a mirror formula?
Define the term Pole.
Define the term Principle focus.
Which of the following has curved reflecting surface?
The spherical mirror used as a rear view mirror in the vehicle is
A converging lens of focal length f is placed at a distance 0.3 m from an object to produce an image on a screen 0.9 m from the lens. With the object and the screen in the same positions, an image of the object could also be produced on the screen by placing a converging lens of focal length.
Visit a nearby hospital. You can also visit the clinic of an ENT specialist, or a dentist. Request the doctor to show you the mirrors used for examining ear, nose, throat and teeth. Can you recognise the kind of mirror used in these instruments?
