PRACTICE WORKSHEET, CH 11, CLASS 6

A. Multiple Choice Questions

1. Shadows form because:
(a) opaque objects reflect light
(b) opaque objects do not allow light to pass through them
(c) light travels in one direction from a source
(d) light bends around an opaque object

2. objects do not allow any light to pass through them.
(a) Transparent
(b) Translucent
(c) Opaque
(d) Luminous

3. Which of the following is a non-luminous body?
(a) Moon
(b) Sun
(c) Bulb
(d) Burning candle

4. The colour of a shadow is :
(a) black
(b) green
(c) grey
(d) cannot say

5. The speed of light in vacuum is :
(a) 3 × 108 m/sec
(b) 2 × 109 m/sec
(c) 1.5 × 108 m/sec
(d) none of these

B. Fill in the Blanks:

1. Light is a form of ……………………. .
2. A glowing tubelight is an example of …………………… source of light.
3. The shadow of an object is always of ………………. colour.
4. The …………………… is a luminous object.
5. Light travels in a ……………….. line.

C. State True or False:

1. The moon is a natural source of light. ……………….
2. Light always travels in a straight line. ……………….
3. Pinhole camera works on the principle of rectilinear propagation of light. ………………….
4. Stars are luminous bodies. …………………
5. Shadow of an object is formed in the direction. opposite to that of the light source. …………….

D. Match the following:

‘A’	‘B’
1. Brick	a. A natural source of light
2. Tubelight	b. Region of partial darkness
3. Sun	c. Shadow cast by heavenly bodies
4. Eclipse	d. An opaque object
5. Penumbra	e. An artificial source of light

E. Write the letter in the blanks given below with the help of corresponding hints.

1. T _ _ _ S _ _ _ _ _T.
Hint: Through these objects, we can see but not very clearly.

2. _ _M _ N _ _ S.
Hint: Sun is in this category of sources of light.

3. S _ R _ _ _.
Hint: We can’t obtain an image without this.

4. R _ _ _ C _ _ _ _ .
Hint: Mirror gives us clear images because of this phenomenon.