Human Eye And C...

An equilateral prism is made of a material of refractive index . The angle of minimum deviation for the prism is

A student can distinctly see the object up to a distance 15 cm. He wants to see the blackboard at a distance of 3 cm. The focal length and power of lens used will be

Directions: In the following question, two statements are given. One is Assertion and the other is Reason. Examine the statements carefully and mark the correct answer accordingly.

Assertion: Blue colour of sky appears due to scattering of blue colour.
Reason: Blue colour has the shortest wavelength in the visible spectrum.

A doctor prescribes spectacles to a patient with a combination of a convex lens of focal length 40 cm and concave lens of focal length 25 cm. The power of spectacles will be

What is the increasing order of the extent of angle changes undergone by the colours of the spectrum during splitting of white light?

_______ is the dark muscular diaphragm that controls the size of the pupil.

An eye specialist prescribes spectacles having a combination of convex lens of focal length 50 cm in contact with a concave lens of focal length 25 cm. The power of this combination of lenses (in dioptre) is

Which of the following defects can be rectified by using cylindrical lenses?

Which of the following phenomena is used in formation of rainbow

The change in focal length of an eye lens is caused by the action of

White colour of the clouds is due to

White light is incident on the interface of the glass and air as shown in the figure. If the green light is just totally internally reflected, the emerging ray in the air contains

The far point of myopic person is 40 cm. To see distant objects clearly, the focal length and the power of the lens used should be

For a prism, the angle of minimum deviation is directly proportional to the

The Sun is visible a little before the actual sunrise because of

For a defective eye, the power of lens required is –2 D. What is the distance beyond which he is not able to see the objects clearly?

The blind spot refers to the area where __________.

Which of the following options represents the angle of deviation for a ray of light passing through a prism?

One cannot see through fog because

Which of the following statements is incorrect?