Question 11 Mark
Fill in the following blanks with suitable words: Night birds have $............$ cones than rods in their eyes.
AnswerNight birds have Fewer cones than rods in their eyes.
Explanation: Night birds have fewer cones and more rods because rods function in less amount of light. Cones function in bright light.
View full question & answer→Question 21 Mark
Fill in the following blanks with suitable words: If you touch your $............$ ear with right hand in front of a plane mirror, it will be seen in the mirror that your right ear is touched with $............$
AnswerIf you touch your Left ear ear with right hand in front of a plane mirror, it will be seen in the mirror that your right ear is touched with left hand.
Explanation: Images formed by a plane mirror are opposite in direction.
View full question & answer→Question 31 Mark
Fill in the following blanks with suitable words: A person 1m in front of a plane mirror seems to be $............ m$ away from his image.
AnswerA person $1m$ in front of a plane mirror seems to be $2m$ away from his image.
Explanation: Image formed by a plane mirror is far behind the mirror as the object is in front of the mirror.
View full question & answer→Question 41 Mark
Braille system was invented by $............$
View full question & answer→Question 51 Mark
The space between the cornea and lens is filled with a liquid called $............$
View full question & answer→Question 61 Mark
In bright light, the size of pupil $............$
View full question & answer→Question 71 Mark
When the mirrors are inclined at $90^\circ ,$ we get $............$ images.
View full question & answer→Question 81 Mark
Mirror is a $............$ surface.
View full question & answer→Question 91 Mark
Paper is a $............$ surface.
View full question & answer→Question 101 Mark
The reflection of light from an uneven surface is called $............$
View full question & answer→Question 111 Mark
The point on the surface at which incident ray strikes is called $............$
View full question & answer→Question 121 Mark
Kaleidoscope is based on the concepts of $............$
View full question & answer→Question 131 Mark
Splitting of light into seven colours is called $............$
View full question & answer→Question 141 Mark
The size of image formed by the plane mirror is $............$ as size of object.
View full question & answer→Question 151 Mark
Reflection from a smooth surface is called $............$ reflection.
View full question & answer→Question 161 Mark
Angle of incidence is always $............$ to the angle of reflection.
View full question & answer→Question 171 Mark
The ray which returns after striking the surface is called $............$ ray.
View full question & answer→Question 181 Mark
A plane mirror forms a $............$ image.
View full question & answer→Question 191 Mark
$............$ is the perpendicular line on the incidence point.
View full question & answer→Question 201 Mark
A mirror has $............$ and $............$ surface.
View full question & answer→Question 211 Mark
The bouncing back of light after it falls on a surface is called $............$
View full question & answer→Question 221 Mark
The ray of light which strikes the reflecting surface is called $............$
View full question & answer→Question 231 Mark
Light is a form of $............$
View full question & answer→Question 241 Mark
Fill in the following blanks with suitable words:
In a movie, the still pictures in proper sequence are projected on the screen usually at the rate of $............$ pictures per second.
AnswerIn a movie, the still pictures in proper sequence are projected on the screen usually at the rate of $24$ pictures per second.
Explanation:
The frame rate for motion pictures is $24$ pictures per second. Frame rate is the rate at which consecutive images are displayed in a display.
View full question & answer→Question 251 Mark
Fill in the following blanks with suitable words: The image of an object persists on the retina of an eye for about $............$ second even after the object has disappeared.
AnswerThe image of an object persists on the retina of an eye for about $\frac1{16}^{th}$ second even after the object has disappeared.
Explanation: The phenomenon is known as Persistence of Vision. The property of this phenomenon is that the image formed on the retina of the eye persists for about $\frac1{16}^{th}$ of a second even after the object has disappeared.
View full question & answer→Question 261 Mark
Fill in the following blanks with suitable words:
The angle of $............$ equals the angle of reflection.
AnswerThe angle of Incidence equals the angle of reflection.
Explanation:
This is by law of reflection. The angle of incidence equals the angle of reflection.
View full question & answer→Question 271 Mark
Fill in the following blanks with suitable words: The size of pupil becomes $............$ when you see in dim light.
AnswerThe size of pupil becomes Large when you see in dim light.
Explanation:
The size of pupil dilates, facilitated by the iris, so that maximum amount of possible light enters the eye and a person views things clearly.
View full question & answer→Question 281 Mark
Fill in the following blanks with suitable words: If the still pictures of a moving object are flashed on our eyes at a rate faster than $............$ pictures per second, the eye perceives the object as moving.
AnswerIf the still pictures of a moving object are flashed on our eyes at a rate faster than $16$ pictures per second, the eye perceives the object as moving.
Explanation:
The is due to the phenomenon Persistence of Vision. The property of this phenomenon is that the image formed on the retina of the eye persists for about $\frac1{16}^{th}$ of a second, hence if $16$ frames are flashed in front of the eyes, they are viewed by the retina as an ongoing action.
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