The angular magnification of the telescope is calculated using the formula M = -fo / fe, resulting in an angular magnification of -21.11, with the negative sign indicating that the image is inverted.
The angular magnification (M) of a telescope can be found with the formula M = -fo / fe,
where fo is the focal length of the objective lens and fe is the focal length of the eyepiece.
For the telescope in question, with an eyepiece focal length of 9.00 cm and the final image at infinity (which indicates that the objective lens's focal length is equal to the separation between the two lenses), the objective's focal length fo is 1.90 m or 190 cm.
Therefore, the angular magnification is M = -(190 cm) / (9 cm) = -21.11.
In this case, the negative sign indicates that the image is inverted. High angular magnification is beneficial for viewing distant celestial objects, making them appear larger and more detailed to the observer.