To calculate the actual size of an object, you can use the following formula, derived from the provided reference: Actual size = image size / magnification.
Here's a breakdown and example:
Understanding the Formula
The relationship between actual size, image size, and magnification is crucial. It's based on a simple concept: magnification enlarges the object. Therefore, to find the real, actual size, you must reverse this process.
- Actual Size: The true physical size of the object.
- Image Size: The size of the object as seen through a magnifying instrument (like a microscope) or on an image (like a photograph).
- Magnification: The factor by which the object's size is increased. This is usually indicated on the magnifying instrument.
Calculation Table
| Variable | Description | Formula |
|---|---|---|
| Actual Size | The real size of the object | Image Size / Magnification |
| Image Size | The size of the object in the image | Actual Size x Magnification |
| Magnification | How much larger the image is than the real object | Image Size / Actual Size |
Example
Let's say you're looking at a cell under a microscope.
- Image Size: You measure the cell's image size under the microscope to be 500 micrometers (µm).
- Magnification: The microscope is set at a magnification of 100x.
To find the actual size of the cell:
Actual Size = Image Size / Magnification
Actual Size = 500 µm / 100
Actual Size = 5 µm
Therefore, the actual size of the cell is 5 micrometers.
Key Takeaway
Remember the formula: Actual size = image size / magnification. Also, be careful that the units of measurement are consistent. If image size is in millimeters (mm) then after calculation the actual size will also be in millimeters.
