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Magnification of a Telescope Calculator

1. What is the Magnification of a Telescope?

Definition: The magnification of a telescope is the ratio of the primary focal length to the eyepiece focal length, calculated using the formula:

\[ M = \frac{F_p}{F_e} \]

Variables:

  • \( M \): Magnification (unitless, real value).
  • \( F_p \): Primary focal length (in millimeters).
  • \( F_e \): Eyepiece focal length (in millimeters).
Explanation: Magnification indicates how much larger an object appears when viewed through the telescope, assuming \( F_p > F_e \) for positive magnification.

2. Importance of Magnification

Details: Magnification is a key parameter in telescope design, determining the apparent size of celestial objects, though it must be balanced with resolving power and field of view.

3. Using the Calculator

Tips: Enter the primary focal length and eyepiece focal length (in millimeters). Click "Calculate" to get the magnification as a real number. Ensure the eyepiece focal length is less than the primary focal length for positive magnification.

Frequently Asked Questions (FAQ)

Q1: What is magnification?
A: Magnification is the factor by which a telescope enlarges the apparent size of an object.

Q2: Why is focal length important?
A: The ratio of the primary focal length to the eyepiece focal length determines the magnification power.

Q3: What units are used?
A: Both focal lengths are measured in millimeters (mm).

Q4: What if the eyepiece focal length is larger?
A: If \( F_e \geq F_p \), the magnification will be zero or negative, which is not typical for a telescope.

Q5: How accurate is this calculator?
A: The calculator is accurate based on the given formula and input values, assuming ideal optical conditions.

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