Skip to main content

NCERT solutions for class 10 science The Human Eye and the Colorful World

NCERT solutions for class 10 science The Human Eye and the Colorful World

Today we will learn ‘The defects of vision and their correction’.

Defects of vision and their correction
The ability to see is called vision.It is also called an eyesight.Vision is known as ‘Drishti’ in Hindi. There are three common defects of vision or defects of the eyes:
  1. Myopia
  2. Hypermetropia
  3. Presbyopia
Myopia (Short-sightedness or nearsightedness)
Myopia is the defect of vision due to which a person cannot see the distant objects clearly, though he/she can see the nearby objects clearly. The far point of an eye suffering from myopia is less than infinity.
 The defect of the eye called myopia is caused:-
  1. Due to thehigh converging power of eye lens because of its short focal length.
  2. Due to the eyeball being too long.
In some cases, in an eye suffering from myopia, the ciliary muscle attached to the eye lens does not relax sufficiently to make the eye-lens thinner to reduce its converging power. So due to the greater converging power of the eye-lens in amyopic eye, the image of a distant object is formed in front of the retina and hence the eye cannot see it clearly.
Myopia is corrected using spectacles containing concave lenses. The concave lens used for correcting myopia should be of such a focal length that it produces a virtual image of the distant object at the far point of the myopic eye. The whole purpose of using a concave lens here is to reduce the converging power of the eye-lens.

Looking for CBSE Class 10 sample papers, NCERT solutions for class 10 science visit www.takshilalearning.com. It will enable you to review the complete subject matter for Class 10 designed by the experts.

Call us : 8800999280/8800999284

Labels:

Comments

Post a Comment

Thank you we will contact ASAP.

Popular posts from this blog

Allotment of DIN (Director Identification Number)

Allotment of DIN (Director Identification Number) CS professional course :  Section 153 of the Companies Act, 2013 read with Rule 9 of the Companies (Appointment and Qualification of Directors) Rules, 2014 Every individual intending to be appointed as a director as a director of a company shall make an application for allotment of Director Identification Number (DIN) to the Central Government in such form and manner and along with such fees as may be prescribed. Rule 9 of Companies (Appointment and Qualification of Directors) Rules, 2014 (1) Every Individual, who is to be appointed as a director of a company shall make an application electronically in Form DIR 3, to the Central Government for the allotment of a DIN along with such fees as provided in the Companies (Registration Offices and Fees) Rules, 2014. (2) The Central Government shall provide an electronic system to facilitate submission of an application for the allotment of DIN through the portal on the MCA21...
Post a Comment
Read more

PURCHASED GOODWILL METHOD UNDER IND AS 103

The acquisition of subsidiaries results in  Goodwill calculation  and also records net assets of the subsidiary at fair value on the date of acquisition. Let’s get answers to all the questions related to Goodwill, valuation of NCI, and impairment relating to them. Q1 – What are the ways in which an entity can make payment for purchase consideration? ANS: – Cash – Share exchange – Deferred payment – Contingent consideration Q2 – How is deferred payment dealt, when it forms part of purchase consideration? ANS:  The deferred payment is discounted to present value and included in the cost of consideration. At the end of each year, the liability is increased by unwinding the discount, until the payment is settled. For example, An amount of Rs. 108,000 was deferred to be paid after 2 years. The discount rate applicable is 8%. The net present value today of Rs. 108,000 is equal to (108,000 * 1) / (1.08) ^2)= Rs. 92,593 included in purchase consideration. A liability of Rs. 92,59...
Post a Comment
Read more

NCERT 12th Class Physics Ohm’s Law and Resistance

NCERT 12th Class Physics Ohm’s Law and Resistance Ohm’s Law Ohm’s law:   It states that “the current flowing through a conductor is directly proportional to potential difference between the ends of the conductor provided physical conditions like temperature, pressure etc.  remain the same”. i.e.   VαI or V = IR Here V is apotential difference,I is current and R is Resistance of the conductor. Resistance:  It is the ability of a conductor to oppose the flow of electric current . SI unit of resistance is ohm. Factors on which resistance of a conductor depends: Nature of the material of the conductor Length of the conductor ‘ l’ Area of cross-section ‘A’ Temperature ie R ∝ l R ∝ 1/A R= 𝜌 l/A Where 𝜌 is resistivity of the material of the conductor. What to study the same topic in Hindi? click on  Physics in Hindi The resistivity  of thematerial of a conductor: 𝜌=RA/ l If we have A=1m 2  and  l ...
Post a Comment
Read more