Light & Optics MCQs with Answers

By mixing all the colors of the visible spectrum of sunlight, we produce ?

• A.Black light
• B.White light
• C.Ultraviolet light
• D.Infrared light

Past Paper MCQ

Which of the following is not a primary color?

• A.Red
• B.Blue
• C.Orange
• D.Yellow

Light travels in a vacuum at the speed of _?

• A.186,282 miles per second
• B.300,000 miles per second
• C.150,000 miles per second
• D.93,000 miles per second

An object which allows some light to travel through it or allows light to pass through partially is called _?

• A.Transparent
• B.Translucent
• C.Opaque
• D.Reflective

Laser is a device which can produce _?

• A.Intense beam of light
• B.Coherent beam of light
• C.Monochromatic beam of light
• D.All of these

What is the efficiency of an electric lamp?

• A.40 to 50%
• B.25 to 30%
• C.10 to 17%
• D.60 to 75%

What is the principal focus of a mirror or lens?

• A.The midpoint of the mirror or lens surface
• B.The centre of curvature of the mirror or lens
• C.The point where parallel rays meet or appear to meet after reflection/refraction
• D.The point where the object is placed to form an image

Which color is produced by adding together yellow and cyan?

• A.Blue
• B.Red
• C.Green
• D.Magenta

The point through which a ray of light passes without changing its path is the _?

• A.Centre of Curvature
• B.Focus
• C.Optical Centre
• D.Pole

A camera uses a _ to form an image on a piece of film at the back.

• A.Concave mirror
• B.Concave lens
• C.Plane mirror
• D.Convex lens