What do you mean by linear magnification?

Linear magnification is the ratio of the size of the image formed by a lens or mirror to the actual size of the object. It shows how much larger or smaller an image is compared to the object.

Formula

Linear Magnification (M) = Image Height (h′) ÷ Object Height (h)

It can also be written as:
M = v ÷ u
Where:
v = image distance, u = object distance

Types

• Positive magnification: Image is upright and virtual.
• Negative magnification: Image is inverted and real.

Example

If an object of height 5 cm produces an image of 10 cm, then:
M = 10 ÷ 5 = 2. The image is magnified two times.

Linear magnification is widely used in optics, microscopes, and cameras.