Write law in a given figure. - Science and Technology 1

Advertisements
Advertisements
One Line Answer

Write law in a given figure.

Advertisements

Solution

Rule I: When the incident ray is parallel to the principal axis, the refracted ray passes through the principal focus.

Concept: Lens
  Is there an error in this question or solution?
Chapter 7: Lenses - Answer the Following

RELATED QUESTIONS

State the position of the object in front of a converging lens if It is used as a magnifying lens.


Draw a ray diagram to show how a converging lens is used as a magnifying glass to observe a small object. Mark on your diagram the foci of the lens and the position of the eye.


Match the columns in the following table and explain them.

Column 1 Column 2 Column 3
Farsightedness
Nearby object can be seen clearly
Bifocal lens
Presbyopia Far away object can be seen clearly Concave lens
Nearsightedness Problem of old age Convex lens

Draw a figure explaining various terms related to a lens.


Distinguish between:

Concave lens and Convex lens.


(i) If the lens is placed in water instead of air, how does its focal length change ? 
(ii) Which lens, thick or thin has greater focal length ?


Write the lens formula explaining the meaning of the symbols used.


The instrument used to observe planets.

Aniket from Std. X uses spectacles. The power of the lenses in his spectacles is - 0.5 dioptre.
Answer the following questions:
  1. State the type of lenses used in his spectacles.
  2. Name the defect of vision Aniket is suffering from.
  3. Find the focal length of the lenses used in his spectacles.

State the nature and position of the object on the principal axis to obtain. A virtual and diminished image.


A converging lens is used to obtain an image of an object placed in front of it. The inverted image is formed between F2 and 2F2 of the lens. Where is the object placed?


From the nature of the refracted rays, shown in the diagram interpret the nature of the lens represented by the dotted line.


Draw the ray diagrams of a converging lens, when the object is placed at a distance greater than twice the focal length of the lens.


Define the focal length.


How does a concave lens act as a ‘diverging lens’?


The image formed by _______ lens is always virtual and small.


Find the odd one out and give its explanation.


Write the name.

The distance between focus and optical centre.


Write an Explanation.

The optical centre of the lens


Write an Explanation.

Principal focus


Write an Explanation.

Focal length


Write an Explanation.

Principal axis


Write scientific reason.

A convex lens is called a converging lens.


Write law in a given figure.


Explain with a ray diagram the position, size, and nature of the various images formed by the convex lens.

An object beyond 2F1.


Explain with a ray diagram the position, size, and nature of the various images formed by a convex lens.

An object is in between F1 and 2F1


Explain with a ray diagram the position, size, and nature of the various images formed by a convex lens.

Object at focus F1


The image formed by a lens is always virtual, erect and smaller in size than an object kept at different positions in front of it. Identify the nature of the lens.


State whether the following statement is True or False

A concave lens can be used to produce an enlarged and erect image.


State whether the following statement is True or False

A convex lens always produces a real image.


Observe the figures given in Figure 15.1 carefully.

The given figures show the path of light through lenses of two different types, represented by rectangular boxes A and B. What is the nature of lenses A and B?


Two different types of lenses are placed on a sheet of newspaper. How will you identify them without touching them?


It was observed that when the distance between an object and a lens decreases, the size of the image increases. What is the nature of this lens? If you keep on decreasing the distance between the object and the lens, will you still be able to obtain the image on the screen? Explain.


A convex lens ‘A’ of focal length 20 cm and a concave lens ‘B’ of focal length 5 cm are kept along the same axis with a distance ‘d’ between them. If a parallel beam of light falling on ‘A’ leaves ‘B’ as a parallel beam, then the distance ‘d’ in cm will be ______.


A point object is placed at a distance of 60 cm from a convex lens of a focal length of 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of:


A convex lens ‘A’ of focal length 20 cm and a concave lens ‘B’ of focal length 5 cm are kept along the same axis with a distance ‘d’ between them. If a parallel beam of light falling on ‘A’ leaves ‘B’ as a parallel beam, then the distance ‘d’ in cm will be ______


A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of :


Distinguish between:

Concave lens and Convex Lens


Share
Notifications



      Forgot password?
Use app×