Q24.A car is fitted with a convex side-view mirror of focal length 20 cm. A second car 2.8 m behind the first car is overtaking the first car at relative speed of 15 m/s. The speed of the image of the second car as seen in the mirror of the first one is : JEE Main 2011 JEE Main Previous Year Paper (1) 1 m/s (2) 10 m/s 15 (3) 15 m/s (4) 101 m/s
What This Question Tests
This question tests the ability to calculate the velocity of an image formed by a convex mirror by differentiating the mirror formula with respect to time.
Concepts Tested
Formulas Used
1/f = 1/v + 1/u
dv/dt = -(v/u)² du/dt
📚 NCERT Sections This Tests
9.15 — Apply Mirror Equation And The Condition:
Physics Class 12 · Chapter 9
9.15 Apply mirror equation and the condition: (a) f < 0 (concave mirror); u < 0 (object on left) (b) f > 0; u < 0 (c) f > 0 (convex mirror) and u < 0 (d) f < 0 (concave mirror); f < u < 0 to deduce the desired result.
9.2 — A 4.5 Cm Needle Is Placed 12 Cm Away From A Convex Mirror Of Focal
Physics Class 12 · Chapter 9
9.2 A 4.5 cm needle is placed 12 cm away from a convex mirror of focal length 15 cm. Give the location of the image and the magnification. Describe what happens as the needle is moved farther from the mirror.
9.1 — A Small Candle, 2.5 Cm In Size Is Placed At 27 Cm In Front Of A Concave
Physics Class 12 · Chapter 9
9.1 A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of the image. If the candle is moved closer to the mirror, how would the screen have to be moved?
📋 Question Details
- Chapter
- Ray Optics
- Topic
- Velocity of image in mirrors
- Year
- 2011
- Shift
- Unknown
- Q Number
- Q24
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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