CBSE Class 10 Science Worksheet
Unit III: Natural Phenomenon - Light- Reflection and Refraction
1.
Choose the correct option: Magnification of real image is always ________.
A)
Positive
B)
Negative
C)
Zero
D)
Either positive or negative
2.
What forms always virtual image?
A)
Convex lens
B)
Concave mirror
C)
Convex mirror
D)
None of these
3.
The angle of incidence for a ray of light passing through the centre of curvature of a concave mirror is :
A)
45°
B)
90°
C)
0°
D)
180°
4.
Find the power of a convex lens of focal length 4 m.
5.
Calculate the focal length of convex lens which produces a virtual image at a distance of 25 cm of an object placed 10 cm in front of it
6.
A converging lens of focal length 5 cm is placed at a distance of 20 cm from a screen. How far from the lens should an object be placed so as to form its real image on the screen ?
A)
-10cm
B)
-5cm
C)
15cm
D)
6.6cm
7.
The focal length of a small concave mirror is 2.5 cm. In order to use this concave mirror as a dentist’s mirror,the distance of tooth from the mirror should be :
A)
2.5 cm
B)
1.5 cm
C)
4.5 cm
D)
3.5 cm
8.
What is the nature of an image formed by a thin convex lens for a distant object?
9.
The phenomenon of splitting of light is known as
A)
Image formation
B)
Dispersion
C)
Lateral inversion
D)
None of the above
10.
Linear magnification produced by a convex lens can be :
A)
less than 1 or more than 1
B)
less than 1 or equal to 1
C)
more than 1 or equal to 1
D)
less than 1, equal to 1 or more than 1
11.
State TRUE/FALSE: Snell's law is valid even when light is incident normally on surface of a refracting medium.
A)
TRUE
B)
FALSE
12.
Choose the correct option: For perfect reflection angle of incidence is _______.
A)
Greater than angle of reflection
B)
Equal to angle of reflection
C)
Less than angle of reflection
D)
None of these
13.
Fill in the blanks: The range of wavelength of visible light is _______ to ________.
14.
Focal length of concave mirror is X times the Centre of curvature. X is
15.
A diverging lens has a focal length of 0.10 m. The power of this lens will be :
A)
10.0 D
B)
+ 1.0 D
C)
– 1.0 D
D)
– 10.0 D
16.
An object 5 cm high is held 25 cm away from a converging lens of focal length 10 cm. Find the position, sizeand nature of the image formed. Also
A)
+15.66cm
B)
16.6cm
C)
+20cm
D)
-16.6cm
17.
Angle of incidence will always be equal to angle of refection
A)
True
B)
False
18.
What happens to the ray of light when it travels from one medium to another having equal refractive indices?
19.
Choose the correct option: When the light rays move from denser to rarer medium then angle of incidence is ________.
A)
Greater than angle of refraction
B)
Equal to angle of refraction
C)
Less than angle of refraction
D)
None of these
20.
Choose the correct option: Unit of the power of the lens is _______.
A)
Dioptre
B)
Metres
C)
Centimeter
D)
Radian
CBSE Class 10 Science Worksheet
Unit III: Natural Phenomenon - Light- Reflection and Refraction
Answers
1.
Option B
2.
Option C
3.
Option C
4.
0.25 D
5.
16.67 cm
6.
Option D
7.
Option B
8.
Real, inverted and highly diminished
9.
Option B
10.
Option D
11.
Option B
12.
Option B
13.
400 nm, 700 nm
14.
Option A
15.
Option D
16.
Option B
17.
Option A
18.
It doesn't bend from its original path.
19.
Option C
20.
Option A
