Formula Centre

Formula guides and key subject rules for every grade and subject, with worked examples and practice.

Grade 10 Life Sciences essentials

Life Sciences • Essential reference • Grade 10

Magnification = image size / actual size
image sizeMeasured size of the image (mm)
actual sizeReal size of the object (mm)

When to use it

Use when comparing microscope images with actual specimens.

Worked example

A 20 mm image of a 2 mm object has magnification 10×.

Common mistakes

  • Mixing measurement units.

Practice question

Find the magnification of a 30 mm image of a 3 mm object.

Grade 11 Life Sciences essentials

Life Sciences • Essential reference • Grade 11

Magnification = image size / actual size
image sizeMeasured size of the image (mm)
actual sizeReal size of the object (mm)

When to use it

Use when comparing microscope images with actual specimens.

Worked example

A 20 mm image of a 2 mm object has magnification 10×.

Common mistakes

  • Mixing measurement units.

Practice question

Find the magnification of a 30 mm image of a 3 mm object.

Grade 12 Life Sciences essentials

Life Sciences • Essential reference • Grade 12

Magnification = image size / actual size
image sizeMeasured size of the image (mm)
actual sizeReal size of the object (mm)

When to use it

Use when comparing microscope images with actual specimens.

Worked example

A 20 mm image of a 2 mm object has magnification 10×.

Common mistakes

  • Mixing measurement units.

Practice question

Find the magnification of a 30 mm image of a 3 mm object.