Question 1 :
A ray of light incident at a point on the principal axis of a convex lens passes undeviated through the lens. What special name is given to this point on the principal axis?<br>
Question 2 :
Concave lens is used in cameras to focus an image of film. Is the statement True or False?<br/>
Question 3 :
A rod is placed in a beaker of full of water. It appears to be bent inside the water. Which of the following property of light is responsible for the rod appearing to be bent?
Question 5 :
The ratio of the size of the image to the size of the object is known as
Question 6 :
A man sees a smallstationary fish deep in a very clear lake and shoots it accurately. He will
Question 7 :
Focal length of a lens is 50 cm. Its power would be :
Question 8 :
Which of the following is not an application of convex lens?
Question 10 :
What is the size of image when position of object is at F, position of image is at infinity and image formed through concave mirror?<br>
Question 11 :
Assertion: Farther the image greater is the magnification.
Reason: Magnification is equal to the ratio of the distance of the object and that of the image.
Question 13 :
A object is placed at 30 cm on the principle axis of the convex lens from the lens and an image is formed 60 cm from the lens. If focal length of the lens is 20 cm then calculate the magnification.
Question 15 :
The image of an object placed on the principal axis of a concave mirror of focal length $12\ cm$ is formed at a point which is $10\ c$ more distance from the mirror than the object. The magnification of the image is
Question 16 :
The least distance of vision of a longsighted person is $60\ cm$. By using a spectacle lens, this distance is reduced to $12\ cm$. The power of the lens is
Question 17 :
An object is kept at 15 cm from a convex mirror of focal length 25 cm. What is the magnification?<br/>
Question 18 :
When a ray of light traveling from vacuum to a medium of refractive index $\mu $, the angle of incidence is twice the angle of refraction. The incident angle is :<br/>
Question 19 :
The power of a lens is a measure of its degree of
Question 20 :
A person cannot see objects clearly beyond $2.0\ m$. The power of lens required to correct his vision will be
Question 21 :
Air has refractive index $1.0003$. Find the thickness of air column which will contain one more wavelength of yellow light of $6000$ $A^0$ than in same thickness of vacuum.
Question 22 :
Three convex lenses are available having focal lengths of $4 cm, 40 cm$ and $4 m$ respectively. Which one could be used as magnifying glass?
Question 23 :
A point object is placed on the principal axis of the convex lens of focal length 20cm at a distance 40 cm to the left on it. The diameter of the lens is 10cm. If the eye is placed 60cm to the right of the lens at a distance h below the principal axis, then max value of 'h' to see the image is
Question 24 :
The glancing angle of incidence is $10^{\circ}$. What will be the glancing angle of reflection?
Question 25 :
Aconvex lens of radii of curvature 20 cm and 30 cm respectively. It is silveredat the surface which has smaller radius of curvature. Then it will behave as $(\mu_g\, = \, 1.5)$