Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 10 Answered

IN MIRRORS AND LENS PLEASE EXPLAIN, WHEN WE WILL TAKE FOCAL LENGTH AS NEGATIVE OR POSITIVE. PLEASE EXPLAIN BOTH IN LENS AND MIRRORS ABOUT OBJECT. IMAGE. FOCAL LENGTH. IMAGE IS REAL AND INVERTED OR IS VIRTUAL AND ERECT AND WHEN WE WILL TAKE THE SIGNS AS POSITIVE AND NEGATIVE.I AM NOT YET CLEAR IN THIS.
Asked by | 19 Mar, 2012, 09:49: AM
answered-by-expert Expert Answer

Generally, the ‘New Cartesian Convention’ is used, according to which all distances are measured from the pole of the mirror. The distances measured in the same direction as the incident light (+ x axis) are taken to be positive, and those in the opposite direction as negative.
The heights measured upwards (above the x-axis) and normal to the principal axis of the mirror are taken as positive, and the heights measured downwards as negative.

similarly in case of lens u can take the sign.
Answered by | 21 Mar, 2012, 10:28: AM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 10 - Physics
how is light made
Asked by infinityupgraded | 13 Apr, 2024, 08:17: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what are the ray diagrams??
Asked by suryamr2019 | 08 Mar, 2024, 04:32: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
student observes the above phenomenon in the lab as a white light passes through a prism. Among many other colours, he observed the position of the two colours Red and Violet. What is the phenomenon called? What is the reason for the violet light to bend more than the red light?
Asked by saurabhjd527 | 30 Jan, 2024, 07:55: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
If rays are coming from a different object to adouble convex lens with two different refractive indices Mu1 and Mu 2 above and below the principal axis, explain how many images will be seen?
question image
Asked by subrasixty | 13 Jan, 2024, 05:05: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
Is object distance always negative in both lens and mirrors?
Asked by nandanagnair | 17 Dec, 2023, 03:44: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
The image of a candle flame placed at a distance of 30 cm from a spherical lens is formed on a screen placed at a distance of 60 cm from the lens. If the height of the flame is 2.4 cm,find the height of its image 
Asked by namish1088 | 16 Nov, 2023, 08:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
describe the refraction taking place in the rainbow formation  
Asked by 0 0 | 19 Oct, 2023, 03:51: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what is the magnification of the image when v=30 cm and u= 15cm
Asked by bubbynaik77 | 29 Sep, 2023, 09:34: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what is defination of light
Asked by gurcharansingh37306 | 10 Sep, 2023, 12:53: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what is concave mirror?
Asked by Shiwani.Sawant | 28 Jul, 2023, 09:42: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×