What is meant by magnification? Write its expression. What is its… - Vidyadip

Question

What is meant by magnification? Write its expression. What is its sign for the (a) real (b) virtual, image?

✓

Answer

Magnification is the ratio of the length of image to the length of the object.
$
m =\frac{1}{ O }
$
It is also given as
$
m =-\frac{ v }{ u }
$
Where, $u$ and $v$ is the object and image distance, respectively.

Hence, we have
1. For real image: $u$ and $v$ are negative. So, $m$ is negative.
2. For virtual image: $u$ is negative and $v$ is positive. So, $m$ is positive.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "[3 Mark Question Answer]" from Reflection of Light→Reflection of Light — all question types→PHYSICS STD 9 question papers→ICSE Board STD 9 question papers→ICSE Board question paper generator→

Similar questions

With the help of a diagram explain how wind energy is converted into electric energy.

Distinguish between fundamental and derived units.

Ashok starts from his house and travels 3 km to reach his school. On finding the school gates closed, he returns to his house. What is?
The displacement of Ashok

A motorcycle of mass 100 kg is running at $10 ms^{-1}$. If its engine develops an extra linear momentum of 2000 Ns , calculate the new velocity of motorcycle.

Why do the dust particles come out of a hanging carpet when it is beaten with a stick?

A block of iron of mass 7.5 kg and of dimensions $12 cm \times 8 cm \times 10 cm$ is kept on a table top on its base of side $12 cm \times 8 cm$. Calculate :

Thrust and
Pressure exerted on the table top

Take $1 kgf = 10 N.$

At sea level, the atmospheric pressure is $1.04 \times 10^5$ Pa. Assuming $g =10 m s ^{-2}$ and density of air to be uniform and equal to 1.3 $kg m ^{-3}$, find the height of the atmosphere.

A hammer exerts a force of 1.5 N on each of the two nails A and B . The area of cross section of tip of nail A is $2 mm^2$ while that of nail B is $6 mm^2$. Calculate pressure on each nail in pascal.

(a) What do you understand by the term weight?
(b) State two important characteristics of weight
(c) State the units of weight in CGS and Sl system.
(d) Name the device used for measuring weight

A test tube weighing 17 gf , floats in alcohol to the level P . When the test tube is made to float in water to the level P, 3 gf of the lead shots are added in it. find the R.D. of alcohol.