Bylens formula v1−u1=f1v1−(−20)1=310v1=310−201v1=60197;v=19760 Magnification of lens (m) is given by m=(uv)=20(19760) velocity of image wrt. to lens is given by vJ/L=m2vO/L direction of velocity of image is same as that of object vO/L=5 m/svI/L=(197×2060×1)2 =1.16×10−3 m/s towards the lens
An object is at a distance of 20 ~m from a convex lens of focal length 0.3 ~m. The lens forms an image of the object. If the object moves away from…
JEE Main 2019 — Physics Optics
2019mcqmedium
An object is at a distance of 20 m from a convex lens of focal length 0.3 m. The lens forms an image of the object. If the object moves away from the lens at a speed of 5 m/s the speed and direction of the image will be
Official previous-year question
Held on 11 Jan 2019 · Verified 6 Jul 2026.
Options
- A
2.26×10−3 m/s away from the lens
- B
0.92×10−3 m/s away from the lens
- C
3.22×10−3 m/s towards the lens
- D
1.16×10−3 m/s towards the lens
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