Cornea

Q.

What is meant by the power of accommodation of the eye?

Q.

What is the lens of the eye?

Q. Glucose on reaching the cells reacts with oxygen to release energy. This process is called _____ .

1. breathing
2. respiration
3. circulation
4. excretion

Q. How do we see objects around us?

1. The light from our eyes illuminates the object.
2. Every object emits light toward our eyes.
3. Light reflects off the object and reaches our eyes.
4. Light reflects off our eyes and falls on the object.

Q.

Light does not travel in a straight line.

1. True
2. False

Q.

A circular object when kept between a small source of light and a screen, casts a sharp shadow on the screen.

This experiment proves:

1. Rectilinear propagation of light

2. Laws of reflection

3. Wave nature of light

4. Laws of refraction

Q.

Focal length of eye lens is

1. fixed

2. variable

3. sometimes fixed and sometimes variable

4. cannot say

Q.

Digestion of food is a __ change.

Q.

Salts are ionic compounds which dissociate into positively charged ions called anions and negatively charged ions called cations when they are dissolved in an aqueous solution.

1. True

2. False

Q.

Which of the following is/are true for modern periodic table?

1. It is in increasing order of atomic number

2. Isotopes take the same place as the element

3. Allotropes take the same place as the element

4. None of the above

Q. Pupil contracts when light is in abundance.

1. False
2. True

Q.

What is transitional polymorphism?

Q. In a human eye, helps the to contract and expand and thereby controls the amount of light entering our eye.

1. eyelens
2. ciliary muscle
3. iris
4. pupil

Q.

If one root of the equation $2x^2+ax+6=0$ is $3$, then find the value of $a$

1. -8

2. 7

3. 3

4. -5

Q. The ability of eyelens to change its to form sharp images is called the power of accommodation.

1. texture
2. focal length
3. colour

Q. Question 12
When light rays enter the eye, most of the refraction occurs at the

(a) crystalline lens
(b) outer surface of the cornea
(c) iris
(d) pupil

Q. Arrange the following in the order in which a light ray travels to enable vision in the human eye.

1. External light
2. Cornea
3. Pupil
4. Eye lens
5. Retina

Q.

A straight path along which light travels is called a

1. Convergent beam of light

2. Ray of light

3. Divergent beam of light

4. None of these

Q. The amount of light entering our eye is controlled by .

1. cornea
2. retina
3. eyelens
4. iris

Q. The cornea is the transparent front part of the eye that covers the iris, pupil and other parts of the eye.

1. False
2. True