Find the distance of the image when an object is placed on the principal axis at a distance of 10 cm. In front of concave mirror whose radius of curvature is 8 cm

To find the distance of the image when an object is placed on the principal axis in front of a concave mirror, you can use the mirror equation:

1/f = 1/v - 1/u

Where:
f = focal length of the mirror
v = distance of the image from the mirror
u = distance of the object from the mirror

In this case, the object is placed on the principal axis at a distance of 10 cm, and the radius of curvature of the mirror is 8 cm.

Since the mirror is concave, the focal length (f) is half the radius of curvature (R):

f = R/2 = 8 cm / 2 = 4 cm

Plugging in the values into the mirror equation:

1/4 = 1/v - 1/10

Now, let's solve this equation to find the distance of the image from the mirror (v):

Multiply both sides by 40v:

10v = 40 - 4v

Add 4v to both sides:

14v = 40

Divide both sides by 14:

v = 40/14

v ≈ 2.857 cm

Therefore, the distance of the image when an object is placed on the principal axis at a distance of 10 cm in front of a concave mirror with a radius of curvature of 8 cm is approximately 2.857 cm.