Ray Optics And Optical Instruments

The magnification for a concave mirror is given by: where is the image distance and is the object distance. We are given that for a real image, so: This implies: The mirror equation is: For a concave mirror, the focal length is related to the radius of curvature by: Substitute cm into the mirror equation: Using the relation , substitute this into the equation: Simplifying: Solving for : Thus, the object should be placed 180 cm from the mirror.

When dealing with lenses, it's important to understand how they form images of objects placed at various positions relative to the lens. For a concave lens, which is also known as a diverging lens, the properties of the image formed are consistent:

• Virtual: The image formed by a concave lens is not actuable on a screen. Virtual images are formed on the same side of the lens as the object.
• Upright: The image retains the same orientation as the object, so it appears in the same upright direction.
• Diminished: The image is smaller than the object due to the lens's diverging properties.

Therefore, for a concave lens, the image of an object will be virtual, upright, and diminished.