A concave mirror produces three times magnified real images of an object placed at $10cm$ in front of it. Where is the image located?
Answer
330k+ views
Hint: We know concave mirror is also known as converging mirror. If the image formed is real then it is always inverted. Also we have to keep in mind the sign conventions while doing the calculations that are all the distance to the left of the pole are taken negative.
Complete step by step solution:
The mirror formula is given as $\dfrac{1}{v}+\dfrac{1}{u}=\dfrac{1}{f}$ and magnification is gives as, $m=\dfrac{height\,\,of\,\,image}{Height\,\,of\,\,object}$
In concave mirror the real image is always inverted so by the question, magnification $m=-3,\,\,also\,\,u=-10cm,\,v=?$
We know that formula for magnification is spherical mirror’s is $m=\dfrac{-v}{u}$
Putting the values of $m=-3$ and $u=-10\,\,in\,\,m=\dfrac{-v}{u}$,
Therefore, \[-3=-\dfrac{v}{(-10)}\]
$v=-30cm$
I$\to $ Image
O$\to $ Object
P$\to $ Pole
Note: Basic sign convention for the spherical mirror are
1. If a virtual image is formed (i.e. behind the mirror) then \[v\] is positive.
2. If a real image is formed (i.e. in front of mirror) then \[v\] is negative.
3. Object distance \[u\] is always negative in the case of a spherical mirror as it is on the left side of the mirror.
4. Focal length of the concave mirror is negative. It is because focus is in front of mirror
5. Focal length of the convex mirror is positive. It is because focus is behind the mirror.
6. In magnification formula of $m=\dfrac{-v}{u}$ for spherical mirrors, if \[m\] is positive, it means image formed is virtual and erect and if \[m\] is negative it means image formed is real and inverted.
Complete step by step solution:

The mirror formula is given as $\dfrac{1}{v}+\dfrac{1}{u}=\dfrac{1}{f}$ and magnification is gives as, $m=\dfrac{height\,\,of\,\,image}{Height\,\,of\,\,object}$
In concave mirror the real image is always inverted so by the question, magnification $m=-3,\,\,also\,\,u=-10cm,\,v=?$
We know that formula for magnification is spherical mirror’s is $m=\dfrac{-v}{u}$
Putting the values of $m=-3$ and $u=-10\,\,in\,\,m=\dfrac{-v}{u}$,
Therefore, \[-3=-\dfrac{v}{(-10)}\]
$v=-30cm$
I$\to $ Image
O$\to $ Object
P$\to $ Pole
Note: Basic sign convention for the spherical mirror are
1. If a virtual image is formed (i.e. behind the mirror) then \[v\] is positive.
2. If a real image is formed (i.e. in front of mirror) then \[v\] is negative.
3. Object distance \[u\] is always negative in the case of a spherical mirror as it is on the left side of the mirror.
4. Focal length of the concave mirror is negative. It is because focus is in front of mirror
5. Focal length of the convex mirror is positive. It is because focus is behind the mirror.
6. In magnification formula of $m=\dfrac{-v}{u}$ for spherical mirrors, if \[m\] is positive, it means image formed is virtual and erect and if \[m\] is negative it means image formed is real and inverted.
Last updated date: 02nd Oct 2023
•
Total views: 330k
•
Views today: 5.30k
Recently Updated Pages
10 Examples of Evaporation in Daily Life with Explanations

10 Examples of Friction in Our Daily Life

Difference between hardware and software

What is the Full Form of DNA and RNA

10 Advantages and Disadvantages of Plastic

What are the Difference Between Acute and Chronic Disease

Trending doubts
How do you solve x2 11x + 28 0 using the quadratic class 10 maths CBSE

Fill the blanks with the suitable prepositions 1 The class 9 english CBSE

Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE

Difference Between Plant Cell and Animal Cell

One cusec is equal to how many liters class 8 maths CBSE

The equation xxx + 2 is satisfied when x is equal to class 10 maths CBSE

What is the color of ferrous sulphate crystals? How does this color change after heating? Name the products formed on strongly heating ferrous sulphate crystals. What type of chemical reaction occurs in this type of change.

Give 10 examples for herbs , shrubs , climbers , creepers

Change the following sentences into negative and interrogative class 10 english CBSE
