Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
Concepts Of Physics MCQ Edition [Volume 1]PhysicsGeometrical Optics

A converging lens of focal length 15 cm and a converging mirror of focal length 10 cm are positioned 50 cm apart. A pin of length 2.0 cm is kept 30 cm from the lens on the side farther from the mirror. Determine the position and the size of the final image.

Options

  1. AAt the object itself, of size 4.0 cm
  2. B10 cm from the mirror, of size 1.0 cm
  3. C30 cm from the lens towards the mirror, of size 2.0 cm
  4. DAt the object itself, of size 2.0 cm

Correct answer

D. At the object itself, of size 2.0 cm

Step-by-step solution

For the first refraction through the converging lens: Object distance, u₁ = -30 cm Focal length, f₁ = +15 cm Using the lens formula, 1 v₁ - 1 u₁ = 1 f₁ 1 v₁ - 1 -30 = 1 15 v₁ = +30 cm Magnification, m₁ = v₁ u₁ = 30 -30 = -1 The first image is formed 30 cm to the right of the lens. For the reflection from the converging (concave) mirror: Distance between the lens and the mirror is 50 cm . Object distance for the mirror, u₂ = -(50 - 30) = -20 cm Focal length of the mirror, f₂ = -10 cm Using the mirror formula, 1 v₂ +

Practice Geometrical Optics on Quantrex Academy →

More from Geometrical Optics

A concave mirror with a radius of curvature of 40 cm is positioned in front of an illuminated point source at a distance of 30 cm from it. Determine the location of the image.A 1 cm object is placed perpendicular to the principal axis of a convex mirror of focal length 7.5 cm . Determine its distance from the mirror if the resulting image is 0.6 cm in sA candle flame 1.6 cm high is imaged in a ball bearing of diameter 0.4 cm . If the ball bearing is 20 cm away from the flame, determine the location and the height of the image.A concave mirror produces an image of a 20 cm high object on a screen located 5.0 m from the mirror. The height of the image is 50 cm . Determine the focal length of the mirror andA concave mirror possesses a focal length of 20 cm . Determine the position or positions of an object such that the image-size is double the object-size.An object that is 3 cm tall is positioned at a distance of 7.5 cm from a convex mirror with a focal length of 6 cm . Determine the location, size, and nature of the image formed.As depicted in the figure, a U-shaped wire is situated in front of a concave mirror with a radius of curvature of 20 cm . Calculate the total length of the image.Determine the diameter of the image of the moon produced by a spherical concave mirror having a focal length of 7.6 m . The moon's diameter is 3450 km and the distance between the Full Geometrical Optics list All Concepts Of Physics MCQ Edition [Volume 1] PYQs