An object is placed 50 cm in front of a concave mirror with a focal length of 25 cm. What is the magnification?
A) -0.50
B) -1.0
C) -1.5
D) -2.0
E) -2.5

Question

Quizplus · Accepted Answer

The formula for magnification is M = -v/u, where v is the image distance and u is the object distance. Given that the object distance is 50 cm and the focal length is -25 cm (since it's concave), we can solve for the image distance:
1/f = 1/v - 1/u
1/-25 = 1/v - 1/50
-2/50 = 1/v
v = -25 cm

Now we can plug in the values for v and u to find the magnification:
M = -v/u = -(-25)/50 = -0.5
Since the magnification is negative, it means that the image is inverted compared to the object. And since the magnification is less than 1, it means that the image is smaller than the object, which makes sense since the mirror is concave. Therefore, the best choice is B.

An Object Is Placed 50 Cm in Front of a Concave