1. The point on the principal axis where all the incident rays ,parallel to the principal axis actually meet after reflection from the concave mirror

2. Concave mirrors

5. It means ratio of speed of light in air to the speed of light in diamond is equal to 2.42

7.focal length =32/2 = 16 cm

8. Two reasons

i. It always produced erect and virtual image

ii. The size of the image is smaller then the object.

Both of the above reason allows the driver to have a wider view of the traffic behind the vehicle in small mirror

9. The paper burns due to converging of the light at that point.

10. Refractive index of an optical medium is ratio speed of the light in air to the speed of the light in the optical medium

11. Absolute refractive index of a medium is defined as the ratio of the velocity of light in vacuum to the velocity of light in the medium. If c is the velocity of light in vacuum and v in the medium, then n = c/v

i.Headlights of a car.

ii.Side/rear view mirror of a vehicle.

iii.Solar furnace.

Support your answer with reason.

1. a. Concave mirror

b. convex mirror

c. concave mirror

2.

Spherical Mirror formula is given as

$ \frac {1}{f} = \frac {1}{v} + \frac {1}{u}$

For a plane mirror, $f = \infty$ , v = v , u = -v

Applying these to Mirror formula

$\frac {1}{\infty} = \frac {1}{v} + \frac {1}{-v}$

$0 = 0$

Hence mirror formula holds good for plane mirrors too.

3.

Here, linear magnification (m) = - 3 (Negative sign for real image, which is inverted)

Object distance(u)=-10 cm

Image distance =x

Now $ m= -\frac {v}{u}$

or v =3u =-30 cm

The image is located at 30 cm in front of the mirror.

4. Refractive index is given by

$n= \frac { speed \; light \; in \; air}{speed \; light \; in \; glass}$

$1.5 = \frac {3 \times 10^8 }{x}$

$x=2 \times 10^8 $

5. Concave mirror

6. $Power = \frac {1}{f(m)}$

$f(meter) = \frac {1}{power} = -.5 m $

f=-50 cm. It is a concave lens

7. $n_{gw}= \frac {n_{ga}}{n_{wa}}$

$= \frac {3/2}{4/3} = \frac {9}{8}$

8. f=250 mm = .25 m

$Power = \frac {1}{f(m)} = 4 D$

9.

i.The image is always virtual and erect.

ii.The image is highly diminished or point sized.

iii.It is always formed between F and P.

iv. The object and image are on opposite sides of mirror.

10.

A concave mirror produces a magnified image when the object is placed in front of the mirror:

i.between its pole and focus

ii.between the focus and centre of curvature

For Ist one the image is virtual and erect, whereas in second the image is real and inverted.

11.

linear magnification is the ratio of the size of the image to the size of the object . It is denoted by Letter m.

For a mirror ,formula is given

$m = - \frac { v }{ u}$

For a lens ,formula is given

$m = - \frac { v }{ u}$

If the image formed is virtual then the magnification has positive value and in case of real images, it is negative

Given below are the links of some of the reference books for class 10 Science.

- Oswaal CBSE Question Bank Class 10 Hindi B, English Communication Science, Social Science & Maths (Set of 5 Books)
- Combo Pack: Science for Class 10 () Lakhmir Singh
- Together with CBSE/NCERT Practice Material Chapterwise for Class 10 Science
- Mastering Numericals and Objectives of Physics for Class X

You can use above books for extra knowledge and practicing different questions.

Class 10 Maths Class 10 Science