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Question
What is the least distance of distinct vision for a normal human eye?
Solution
The least distance for distinct vision for a normal human eye is about 25 centimeters.
RELATED QUESTIONS
Write the function of the following part of the human eye: ciliary muscles
How does the eye regulate the amount of light that falls on the retina?
Myopia is an example of ______.
Draw a neat and labelled diagram of the structure of the human eye.
The optical prescription for a pair of spectacles is :
Right eye : −3.50 D
Left eye : −4.00 D
Which is the weaker eye?
A person got his eyes tested by an optician. The prescription for the spectacle lenses to be made reads :
Left eye : +2.50 D
Right eye : +2.00 D
State whether these spectacle lenses will converge light rays or diverge light rays.
What kind of lens is present in the human eye?
What is the:
near point of a normal human eye?
Fill in the following blank with suitable words:
When light is dim, the pupil becomes................
How is the amount of light entering the eye controlled?
What happens to the eye when you enter a darkened cinema hall from bright sunshine? Give reason for your answer.
There are two types of light-sensitive cells in the human eye:
To what is each type of cell sensitive?
Explain why, we cannot see our seats first when we enter a darkened cinema hall from bright light but gradually they become visible.
The human eye possesses the power of accommodation. This is the power to:
(a) alter the diameter of the pupil as the intensity of light changes
(b) distinguish between lights of different colours
(c) focus on objects at different distances
(d) decide which of the two objects is closer.
Which parts of the eye cause rays of light to converge on the retina?
Why does the eye-lens not have to do all the work of converging incoming light rays?
fill in the following blank with suitable word:
A person is short-sighted if his eyeball is too............Spectacles with a .............lens are needed. A person is long-sighted if his eyeball is too............Spectacles with a ................lens are needed. These focus light rays exactly on to the..........
A man driving a car can read a distant road sign clearly but finds difficulty in reading the odometer on the dashboard of the car. Which of the following statement is correct about this man?
(a) The near point of his eyes has receded away.
(b) The near point of his eyes has come closer to him.
(c) The far point of his eyes has receded away.
(d) The far point of his eyes has come closer to him.
Fill in the following blank with suitable word:
Having two eyes gives a ................field of view.
Five persons A, B, C, D and E have diabetes, leukaemia, asthma, meningitis and hepatitis, respectively.
Which of these persons can donate eyes?
The region in the eyes where the rods and cones are located is the
Mention if the following statement is true (T) or false (F) Give reason.
Short-sightedness and hyperopia are one and the same thing
With reference to the functioning of the eye, answer the question that follow:
Name the two structure in the eye responsible for bringing about the change in the shape of the lens.
Differentiate between:
Yellow spot and Blind spot.
Choose the Odd One Out:
Long answer question
Draw the neat labelled diagram of the Sectional view of the human eye.
Draw a scientifically correct labelled diagram of a human eye and answer the questions based on it:
- Name the type of lens in the human eye.
- Name the screen at which the maximum amount of incident light is refracted?
- State the nature of the image formed of the object on the screen inside the eye.
For a healthy human eye, the distant point is infinite distance.
Vision defect that increases distance between the lens of the eye and retina of the eye is termed as myopia.
Write an Explanation.
Power of accommodation
The following figure show the change in the shape of the lens while seeing distant and nearby objects. Complete the figures by correctly labelling the diagram.
Complete the paragraph by choosing the right options given below.
(minimum, near point, 25 cm, farthest, farthest distance, far point)
The _______ distance of an object from a normal eye, at which it is clearly visible without stress on the eye, is called the minimum distance of distinct vision. The position of the object at this distance is called the _______ of the eye, for a normal human eye, the near point is at _______. The _______ distance of an object from a human eye, at which it is clearly visible without stress on the eye is called _______ of distinct vision. The position of the object at this distance is called the _______ of the eye.
The image formed on the retina of the human eye is ____________.
Assertion: Blind spot is a small area of the retina which is insensitive to light where the optic nerve leaves the eye.
Reason: There are no rods or cones present at the junction of the optic nerve and retina in the eye.
A person cannot see distinctly objects kept beyond 2 m. This defect can be corrected by using a lens of power
Boojho while waving his hand very fast in front of his eyes, observes that his fingers appear blurred. What could be the reason for it?
In human eye the part which allows light to enter into the eye is ______.
Match the following:
| Column - I | Column - II |
| 1. Retina | a. Pathway of light |
| 2. Pupil | b. Far point comes closer |
| 3. Ciliary muscles | c. near point moves away |
| 4. Myopia | d. Screen of the eye |
| 5. Hypermetropia | f. Power of accommodation |
Explain the role of the part of human eye responsible for power of accommodation of human eye.
| Column I | Column II | ||
| 1 | Retina | a | Path way of light |
| 2 | Pupil | b | Far point comes closer |
| 3 | Ciliary muscles | c | near point moves away |
| 4 | Myopia | d | Screen of the eye |
| 5 | Hypermetropia | e | Power of accomodation |
Match the following:
| Column - I | Column - II |
| 1. Retina | a. Path way of light |
| 2. Pupil | b. Far point comes closer |
| 3. Ciliary muscles | c. near point moves away |
| 4. Myopia | d. Screen of the eye |
| 5. Hypermetropia | e. Power of accommodation |
Match the following:
|
Column - I |
Column - II | ||
| 1 | Retina | a | Path way of light |
| 2 | Pupil | b |
far point comes closer |
| 3 | Ciliary muscles | c |
near point moves away |
| 4 | Myopia | d | Screen of the eye |
| 5 | Hypermetropia | e | Power of accommodation |
Name the following:
Kind of retinal cells sensitive to dim light.
Name the following:
Capacity of the eye to focus at different distances.
