Question

a concave mirror produces three time magnified (enlarged) real image of an object placed at 10cm in front of it. where is the image located ​

Answer 1

Answer:

At v = -30cm (image distance)

Explanation:

We are given that,

Image is 3 times magnified the real image M = -3

U = - 10 cm [•°• U is object distance taken from the pole of the mirror]

By using the Magnification formula of mirror

$m = - \frac{ v}{u} \\ \\ - 3 = - \frac { v}{ (- 10)} \\ \\ v = - 30cm$

•°• Image is located at 30 cm distant from the mirror.

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What is meant by magnification ?

• Magnification is basically the ratio of the height of the image formed of the object to the height of the object.

• In concave mirror the ratio is negative because of the Cartesian sign convention.

• According to it , The distances from the (pole)mirror towards the object are taken as negative and the distances from the (pole) mirror to the opposite side are taken as positive.

Answer 2

Answer:

Given:

• a concave mirror

• magnification 3 times

• object distance = -10cm  (sign by convention)

• To find :   image distance (v) = ?

Formula:  $\dfrac{1}{v}+\dfrac{1}{u}=\dfrac{1}{f}$

$Magnification=\dfrac{-v}{u}$

Solving question:

    we are given the object distance(u) and magnification from equating these two we can get answer

Solution:

    $magnification=\dfrac{-v}{u}\\\\\implies -3 = \dfrac{-v}{-10}\\\\\implies -3=\dfrac{v}{10}\\\\\implies v=-30cm$

v = -30cm

Thus, the image distance is -30cm