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The magnification produced by a spherical mirror is +0.75. The image is:
Virtual, erect and diminished
Virtual, erect and enlarged
Real, inverted and diminished
Real, inverted and enlarged
Virtual, erect and diminished
The magnification (m) of a spherical mirror is given by the ratio of the height of the image to the height of the object, or the negative ratio of the image distance to the object distance. A positive magnification (+0.75) indicates that the image is virtual and erect, while a magnitude less than 1 (тИгmтИг<1) signifies that the image is diminished in size.
The magnification (m) of a spherical mirror is given by the ratio of the height of the image to the height of the object, or the negative ratio of the image distance to the object distance. A positive magnification (+0.75) indicates that the image is virtual and erect, while a magnitude less than 1 (тИгmтИг<1) signifies that the image is diminished in size.
Think of looking through a wide-angle security mirror in a hallway or the passenger-side rearview mirror of a car: you see everything upright (erect and virtual) but smaller in size (diminished) so that a wide field of view fits into a compact mirror surface.
V-E-P: Virtual is Erect and Positive (m>0). R-I-N: Real is Inverted and Negative (m<0).
m=hoтАЛhiтАЛтАЛ=тИТuvтАЛ тАФ Magnification formula for spherical mirrors
m>0 тАФ Indicates virtual and erect image
тИгmтИг<1 тАФ Indicates diminished (smaller) image
For spherical mirrors, magnification m=тИТuvтАЛ=hoтАЛhiтАЛтАЛ. A positive sign for m implies hiтАЛ and hoтАЛ have the same sign, meaning the image formed is erect (above the principal axis) and therefore virtual (since real images formed by mirrors are always inverted with a negative magnification). Furthermore, since the absolute value тИгmтИг=0.75 (which is less than 1), the height of the image is smaller than the height of the object, making the image diminished. A convex mirror always produces virtual, erect, and diminished images for all real positions of the object, resulting in a positive magnification less than 1.
A positive sign of magnification (+) always signifies a virtual and erect image.
A magnitude of magnification less than 1 (тИгmтИг<1) denotes a diminished image.
Convex mirrors always produce virtual, erect, and diminished images for any real object position, giving 0<m<1.
Concave mirrors can produce virtual and erect images only when the object is placed between the pole and the principal focus, but in that case, the image is enlarged (m>1).
Convex mirrors provide a wider field of view due to outward curvature.
Convex mirrors do not form real images on a screen and cannot be used to focus sunlight to a point for heating.
Rear-view mirrors in cars and bikes
Security mirrors in departmental stores and blind turns
If m=тИТ1, the image is real, inverted, and of the exact same size as the object (formed at 2F in a concave mirror).
If m>1 with a positive sign, the image is virtual, erect, and magnified (formed by a concave mirror when object is within focus).
A is correct тАФ A magnification of +0.75 indicates that the image is virtual, erect, and diminished in size, which is characteristic of a convex mirror.