Transparency

Q. The objects which do not allow the light to pass through them are called:

1. Transitional
2. Translucent
3. Opaque
4. Transparent

Q.

What do we mean by transparent substance?

1. The materials, through which objects can be seen.

2. Sometimes the object can be seen through and sometimes we cannot.

3. The material through which we cannot see.

4. The materials, through which objects can be seen, but not clearly.

Q. The object through which light passes partially is called object.

1. a transparent
2. a translucent
3. an opaque

Q.

How can you make paper translucent?

Q. Take a glass and apply paint on it then the object changes from:

1. translucent to opaque
2. transparent to translucent
3. opaque to transparent
4. transparent to opaque

Q. Materials through which light can pass easily are called transparent materials.

1. True
2. False

Q. Colour of a transparent object depends on the colour of light it transmits.

1. True
2. False

Q.

8. Why a shopkeeper prefer to keep biscuits and sweets in a glass or plastic container?

Q.

Rubber is a translucent object.

1. True
2. False

Q.

What is meant by (a) transparent materials, (b) translucent materials, and (c) opaque materials ? Give two examples each of transparent, translucent and opaque materials

Q.
During summer holidays, a group of children collected a lump of salt, green grass, broken glass piece, a small thermocol box, pen, iron nail, glass marbles, hair, naphthalene ball, a piece of sugar candy (mishri) and tried to group them on the basis of properties given in table below. Help them in filling the Table.​

​

Name of the material​	Appearance (Hard/soft)​	Transparency​ (Transparent/Translucent/​ Opaque)​	Floats/ Sinks in water​	Soluble/ Insoluble in water​
​	​	​	​	​

Q.

Question 4

Boojho found a bag containing the following materials:

(i) Mirror

(ii) Paper stained with oil

(iii) Magnet

(iv) Glass spectacles

Help Boojho in finding out the material(s) which is/are opaque.

(a) Only (i) (b) Only (iv) (c) (i) and (iii) (d) (i) and (iv)

Q.

A block of wood was placed in the path of light. It completely blocked the light to form a shadow. This is because wood block is ____.

1. translucent

2. opaque

3. conductor

4. transparent

Q. Which among the following materials is lustrous, hard and opaque?

1. Rubber
2. Wood
3. Tin
4. Plastic

Q. _______ is an example of an opaque material.

1. Water
2. Glass
3. Cardboard
4. Oil paper

Q. The velocity of light in glass is __________than that in diamond.

Q.

The solubility of gases in a liquid decreases with a rise in temperature.

1. True
2. False

Q. Materials through which one can see objects are opaque in nature.

1. True
2. False

Q.

You are provided with the following materials

1. magnifying glass
2. mirror
3. stainless steel plate
4. glass tumbler

Which of the above materials will you identify as transparent?

1. (i) and (ii)

2. (i) and (iii)

3. (i) and (iv)

4. (iii) and (iv)

Q.

What are ‘translucent’ objects? Give two examples.

Q.

A translucent material allows all the light to pass through and therefore does not cast any shadow.

1. True
2. False

Q. Karen saw the following objects on his table. Help him pick the right option below.

1. A is tranparent
2. B is opaque
3. A is translucent
4. C is tranparent

Q. Which property is responsible for us being able to see outside glass windows?

1. Transparency
2. Lustre
3. Sonority
4. Malleability

Q. Which statement is correct about the tinted glasses used in cars?

1. They absorb all the light
2. They are see-through
3. None of the above
4. They reflect all light

Q. A saturated solution is one which can dissolve more of the solute at a given temperature.

1. True
2. False

Q.

What is the density of 5 litres of water having mass 5 kg?

1. $100kg/m^3$

2. $500kg/m^3$

3. $750kg/m^3$

4. $1000kg/m^3$

Q. Which among the following is a transparent material?

1. Brick
2. Wood
3. Clear glass
4. Cardboard

Q.

Solids can be compressed easily when pressed.

1. True
2. False

Q.

When we go in a mall especially at cloth shop, we find that the front wall of the shop is made up of glass through which we can see the clothes kept inside as well as there are mannequin (dummies wearing clothes) kept in front of the wall which attracts us to go inside the shop. By which property of glass can we see the objects behind the glass?

1. Transparency

2. Malleability

3. Hardness

4. Conductivity

Q.

Encircle the odd one out and give reasons for your choice.

A plastic jar, coconut oil, notebook , a bag of rice, aluminum