Science
Light & Optical Instruments
Grade 8 · Middle School
Answer every question first, then press Finish to see your score and explanations.
- Question 1 of 20Easy
Light travels in a ... manner.
- Question 2 of 20Easy
In the reflection of light, the angle of incidence equals the angle of ...
- Question 3 of 20Easy
The image formed by a plane mirror is ...
- Question 4 of 20Easy
Light traveling from air into water is refracted ...
- Question 5 of 20Easy
A concave mirror is ...
- Question 6 of 20Easy
A convex lens is ...
- Question 7 of 20Medium
The nature of the image formed by a convex lens depends on ...
- Question 8 of 20Medium
The general formula for mirrors and lenses is ...
- Question 9 of 20Medium
The power of a lens (P) is given by ... and is measured in diopters.
- Question 10 of 20Medium
The part of the eye that receives the image is the ...
- Question 11 of 20Medium
Nearsightedness (myopia) can be corrected with a ... lens.
- Question 12 of 20Medium
Farsightedness (hyperopia) can be corrected with a ... lens.
- Question 13 of 20Medium
A simple optical instrument that uses a single convex lens to view small objects is ...
- Question 14 of 20Medium
The image formed on the retina of the eye is ...
- Question 15 of 20Hard
An object is 30 cm in front of a concave mirror with a focal length of 10 cm. The image distance is ...
- Question 16 of 20Hard
An object is 20 cm in front of a convex lens with a focal length of 10 cm. The image distance and its nature are ...
- Question 17 of 20Hard
A convex lens has a focal length of 50 cm. Its power is ...
- Question 18 of 20Hard
A nearsighted person whose far point is 100 cm needs glasses with a power of ...
- Question 19 of 20Hard
A microscope is made of ...
- Question 20 of 20Hard
A concave lens has a focal length of 25 cm. Its power is ...