Please answer all these questions...
Answers
Answer:
1.True
2.False
3.False
4.True
5.True
6.False
7.False
8.False
9.True
10.True
11.False
12.False
13.True
14.True
15.True
Here's your answer. I hope it helps :)
AnswEr :-
________________________
1) Light is a form of radiant energy.
True
- Energy that is transferred in form of electromagnetic radiations is known as Radiant energy. examples of Radiant energy include Light , heat .
________________________
2) A concave mirror is called a diverging mirror.
False
- Concave mirror is converging in nature , while convex mirror is diverging in nature.
________________________
3) A convex mirror is used as a shaving mirror.
False
- Instead of convex mirror , concave mirror is used as shaving mirror. because concave mirrors give enlarged , virtual and erect image when object is placed in between focus and pole of mirror.
________________________
4) A ray of light goes undeviated on passing through the centre of curvature.
True
- When a light ray pass through the centre of curvature of a mirror it is reflected back along the same path without any deviation.
________________________
5) The speed of light through water is 3×10⁸ ms⁻¹.
False
- Speed of light in water is 2.26 × 10⁸ ms⁻¹ , while speed of light in vacuum or air is 3 × 10⁸ ms⁻¹.
________________________
6) A light year is the unit of distance.
True
- A light year is the distance travelled by light in 1 year. i.e, 1 Light year = 10 trillion km .
________________________
7) Light does not travel in a straight line.
False
- Light always travel in straight lines until something comes in its path. When any object hits the light it is reflected or refracted or absorbed .
________________________
8) A virtual image can be obtained on a screen.
False
- A virtual image cannot be obtained on a screen because Light rays do not actually meet at any point , the image is appeared at an imaginary point.
________________________
9) The focus of a convex mirror lies behind the mirror.
True
- The focus of a convex mirror lies in the negative principal axis .
________________________
10) Convex mirrors are used as reflectors in the head lights of Cars .
False
- Concave mirrors are used as reflectors in the head lights of Cars instead of convex mirror , because when a lighted bulb is placed at the focus of a concave mirror a parallel beam of light is produced.
________________________
11) The focal length is always expressed in the units time.
False
- Focal length is a length , hence expressed in units of length like cm , metre , etc.
________________________
12) Linear magnification of a mirror has no units.
True
- Linear magnification of mirror is the ratio of similar quantities like height of image and height of object or of position of image or position of object , therefore there is no unit of magnification.
________________________
13) Convex mirror has a wider field of view as compared to that of concave mirror.
True
- Concave mirror have a wider field of view as it converges the light ray , on the other hand Convex mirror diverges the light ray , so that it can collect rays for a wider view.
________________________
14) A convex mirror gives virtual image whatever may be the position of object.
True
- A convex mirror always gives a virtual and erect image , doesn't matter where the object is placed in front of mirror.
________________________
15) Angle of incidence is sometimes equal to the angle of reflection in case of spherical mirror.
False
- Angle of incidence is always equal to the angle of reflection . this is one of the two laws of reflection. doesn't matter it is a plane mirror or a spherical mirror . Hence, it is false to say that Angle of incidence is sometimes equal to angle of reflection.
________________________