A 2.0-cm-tall candle flame is 2.0 m from a wall. You happen...

Name: Problem 79, Chapter 18: College Physics: A Strategic Approach
Uploaded: 2023-08-08T02:37:02-08:00
Duration: 3 min 38 s
Channel: Narayan Hari
Description: A 2.0-cm-tall candle flame is 2.0 m from a wall. You happen to have a lens with a focal length of 32 cm. How many places can you put the lens to form a well-focused image of the candle flame on the wall? For each location, what are the height and orientation of the image?

A 2.0-cm-tall candle flame is 2.0 m from a wall. You happen to have a lens with a focal length of 32 cm. How many places can you put the lens to form a well-focused image of the candle flame on the wall? For each location, what are the height and orientation of the image?

Key Concepts

Multiple Lens Positions and Bimodal Solutions

In situations where the total distance from the object to the image exceeds four times the focal length of the lens, two distinct lens placements exist that satisfy the lens equation. This condition is critical in problems where a fixed screen is used, as it results in two different sets of object and image distances which both create a focused image on the screen.

Real Image Formation and Orientation

A real image is formed when light from the object converges through the lens to a point on the image plane, and is typically inverted compared to the object. Understanding real image formation is essential for predicting image properties, such as size and orientation, especially when the object, lens, and image screen (or wall) are fixed in position.

Thin Lens Equation

This equation, expressed as 1/f = 1/u + 1/v, relates the focal length of a lens (f) to the distances from the lens to the object (u) and to the image (v). It forms the fundamental basis for solving problems in geometric optics, allowing us to determine where a lens must be placed to form a real, sharp image given a fixed object and image distance.

Magnification

Magnification is defined as m = -v/u, which relates the sizes of the image and object as well as indicating the orientation of the image (with the negative sign signifying that a real image is inverted relative to the object). This concept allows one to calculate the height of the image from that of the object once the object and image distances are known.

Transcript

Please give Ace some feedback