Aagar

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

The image of a small electric bulb fixed on the wall of a room is to be obtained on the opposite wall 3 m away by means of a large convex lens. What is the maximum possible focal length of the lens required for the purpose?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.19 NCERT Solutions for Class 12 Physics Chapter 9 Question-19

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

Answer the following questions: (a) You have learnt that plane and convex mirrors produce virtual images of objects. Can they produce real images under some circumstances? Explain. (b) A virtual image, we always say, cannot be caught on a screen. Yet when we ‘see’ a virtual image, we are obviously bringing it on to the ‘screen’ (i.e., the retina) of our eye. Is there a contradiction? (c) A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is? (d) Does the apparent depth of a tank of water change if viewed obliquely? If so, does the apparent depth increase or decrease? (e) The refractive index of diamond is much greater than that of ordinary glass. Is this fact of some use to a diamond cutter?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.18 NCERT Solutions for Class 12 Physics Chapter 9 Question-18

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

(a) Figure 9.35 shows a cross-section of a ‘light pipe’ made of a glass fibre of refractive index 1.68. The outer covering of the pipe is made of a material of refractive index 1.44. What is the range of the angles of the incident rays with the axis of the pipe for which total reflections inside the pipe take place, as shown in the figure. (b) What is the answer if there is no outer covering of the pipe?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.17 NCERT Solutions for Class 12 Physics Chapter 9 Question-17

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

A small pin fixed on a table top is viewed from above from a distance of 50 cm. By what distance would the pin appear to be raised if it is viewed from the same point through a 15 cm thick glass slab held parallel to the table? Refractive index of glass = 1.5. Does the answer depend on the location of the slab?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.16 NCERT Solutions for Class 12 Physics Chapter 9 Question-16

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

Use the mirror equation to deduce that: (a) an object placed between f and 2f of a concave mirror produces a real image beyond 2f. (b) a convex mirror always produces a virtual image independent of the location of the object. (c) the virtual image produced by a convex mirror is always diminished in size and is located between the focus and the pole. (d) an object placed between the pole and focus of a concave mirror produces a virtual and enlarged image. [Note: This exercise helps you deduce algebraically properties of images that one obtains from explicit ray diagrams.]

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.15 NCERT Solutions for Class 12 Physics Chapter 9 Question-15

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

(a) A giant refracting telescope at an observatory has an objective lens of focal length 15 m. If an eyepiece of focal length 1.0 cm is used, what is the angular magnification of the telescope? (b) If this telescope is used to view the moon, what is the diameter of the image of the moon formed by the objective lens? The diameter of the moon is 3.48 x 106 m, and the radius of lunar orbit is 3.8 x 108 m.

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.14 NCERT Solutions for Class 12 Physics Chapter 9 Question-14

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

A small telescope has an objective lens of focal length 144 cm and an eyepiece of focal length 6.0 cm. What is the magnifying power of the telescope? What is the separation between the objective and the eyepiece?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.13 NCERT Solutions for Class 12 Physics Chapter 9 Question-13

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

A person with a normal near point (25 cm) using a compound microscope with objective of focal length 8.0 mm and an eyepiece of focal length 2.5 cm can bring an object placed at 9.0 mm from the objective in sharp focus. What is the separation between the two lenses? Calculate the magnifying power of the microscope.

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.12 NCERT Solutions for Class 12 Physics Chapter 9 Question-12

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

A compound microscope consists of an objective lens of focal length 2.0 cm and an eyepiece of focal length 6.25 cm separated by a distance of 15 cm. How far from the objective should an object be placed in order to obtain the final image at (a) the least distance of distinct vision (25 cm), and (b) at infinity? What is the magnifying power of the microscope in each case?

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.11 NCERT Solutions for Class 12 Physics Chapter 9 Question-11

Ashok0210

Asked: March 21, 2021In: Class 12 Physics

What is the focal length of a convex lens of focal length 30 cm in contact with a concave lens of focal length 20 cm? Is the system a converging or a diverging lens? Ignore thickness of the lenses.

Class 12 Physics CBSE and UP Board Ray Optics and Optical Instruments Chapter-9 Exercise 9.10 NCERT Solutions for Class 12 Physics Chapter 9 Question-10

Aagar

The image of a small electric bulb fixed on the wall of a room is to be obtained on the opposite wall 3 m away by means of a large convex lens. What is the maximum possible focal length of the lens required for the purpose?

A small telescope has an objective lens of focal length 144 cm and an eyepiece of focal length 6.0 cm. What is the magnifying power of the telescope? What is the separation between the objective and the eyepiece?

What is the focal length of a convex lens of focal length 30 cm in contact with a concave lens of focal length 20 cm? Is the system a converging or a diverging lens? Ignore thickness of the lenses.

Which is the best website providing NCERT Solutions?

NCERT Books

Where can I get NCERT books in PDF format?

NIOS

NCERT Solutions

Sign Up

Sign In

Forgot Password

Tiwari Academy Discussion Latest Questions