Question

If the focal length of a concave mirror is 15 cm,then find the radius of curvature of the mirror
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Answer 1

Answer:

30cm

Explanation:

Find Radius by Focal Length

• Focal length : 15cm
• Focal length : Distance between Focus and Pole.
• Radius in concave Mirror : Distance between centre of curvature and Pole.
• Centre of curvature : 2F
• Radius : 2F
• F : 15
• 2F : F + F = 30

Hope this will help you

Answer 2

Given :-

The focal length of a concave mirror = 15 cm

To Find :-

The radius of curvature of the mirror.

Analysis :-

Here we are given with the focal length of a concave mirror.

In order to find the radius of curvature of the mirror, substitute the given values such that radius is equal to two times the focal length.

Solution :-

We know that,

• r = Radius
• f = Focal length

Using the formula,

$\underline{\boxed{\sf Radius = 2(Focal \ length)}}$

Given that,

Focal length (f) = 15 cm

Substituting their values,

⇒ r = 2(15)

⇒ r = 30 cm

Therefore, the radius of curvature of the mirror is 30 cm.