Light

Q.

The persistence of vision of a normal human eye is:

1. 1/10S

2. 1/16S

3. 1/20S

Q.

Define the distance of distinct vision and give its range.

Q.

Difference between luminous and non-luminous objects.

Q.

Arrange the various colours of white light in order of (i) increasing wavelength (ii) increasing frequency.

Q. Which of the following colour has maximum wavelength?

1. Red
2. Violet
3. yellow
4. Blue

Q.

Differentiate between the Luminous and non-luminous bodies.

Q.

Colours that are obtained by mixing primary colours are called_____

Q. Braille system is a reading and writting system used by:

1. dumb people
2. deaf people
3. blind people
4. illiterate people

Q.

Light cannot bend around the corners by itself.

1. False

2. True

Q. Figure

(a) How does the above experiment show that light travels in a straight line?
(b) Think and write about two everyday situations that tell you that light travels in a straight line.

Q. It is said that light travels in a straight line. How will you prove this? What is the result of this? [3 MARKS]

Q. An opaque object is moved away from a point source of light, then what happens to the umbra?

Q.

Choose the correct options and fill in the blank:

The property of light travelling in a straight line is referred to as the _________ (rectilinear propagation/ circular propagation) of light.

Q.

What is the least distance of distinct vision of the human eye?

Q.

Name the following:

Colours are made by combining two primary colours.

Q. The phenomenon of bouncing back of light is known as __________ of light.