Library / Tools / GCSE physics equation calculator / Magnification
Magnification calculator
Waves
Magnification is the image height divided by the object height. It has no unit.
magnification = image height / object height
This free calculator is for GCSE physics. Choose the quantity you want to find, enter the other values with their units, and it shows the working in the layout used in exams, with the answer to the number of significant figures you choose. The values shown are an example. Change them to your own.
Quantity to find
Working
- Write the equationmagnification = image height / object height
- Substitute the valuesmagnification = 0.06 ÷ 0.012
- Calculatemagnification = 5
- Give the answer to 3 significant figuresmagnification = 5.00
Worked example
Find magnification, the magnification. Given: image height image height = 0.0600 m; object height object height = 0.0120 m.
- Write the equationmagnification = image height / object height
- Substitute the valuesmagnification = 0.06 ÷ 0.012
- Calculatemagnification = 5
- Give the answer to 3 significant figuresmagnification = 5.00
Symbols and units
| Symbol | Quantity | SI unit |
|---|---|---|
| magnification | Magnification | no unit |
| image height | Image height | m |
| object height | Object height | m |
Magnification: rearranged
- To find magnification: magnification = image height / object height
- To find image height: image height = magnification object height
- To find object height: object height = image height / magnification
Exam tip
Both heights must be in the same unit. A value less than 1 means the image is smaller than the object.
Common questions
What is the formula for magnification?
The equation is magnification = image height / object height, where magnification is the magnification; image height is the image height (m); object height is the object height (m).
What units should I use for magnification?
In SI units: magnification in no unit (a ratio), image height in m, object height in m. The calculator also accepts common alternatives such as kilometres, grams or minutes, and converts them for you.
How do I rearrange magnification = image height / object height?
Rearranging gives these forms: to find magnification: magnification = image height / object height. to find image height: image height = magnification object height. to find object height: object height = image height / magnification.
Practise magnification questions
Press the button for a question with random numbers. Work it out on paper first, then type your answer.
Related
More waves equations: Wave speed, Frequency and time period, Refractive index, Snell’s law, Critical angle, Double-slit fringe spacing, Diffraction grating, Intensity. See the full list on the gcse physics equation calculator page.