Olympiad Test: Fibers To Fabric - 1 - Class 6 MCQ

Why is cotton the most desirable fabric for making undergarments?
There are several reasons why cotton is considered the most desirable fabric for making undergarments.
Absorbent:
- Cotton is known for its high absorbency, making it an ideal choice for undergarments.
- It can absorb sweat and moisture from the body, keeping the wearer feeling dry and comfortable.
- This absorbent property also helps prevent the growth of bacteria and unpleasant odors.
Dull:
- Cotton fabric has a natural dull appearance, which is preferred for undergarments.
- The dullness of cotton helps to minimize transparency, ensuring privacy and modesty.
Shining:
- Cotton is not shiny, which is a desirable characteristic for undergarments.
- Shiny fabrics can draw attention and may not provide the level of discretion needed for undergarments.
Strong:
- Cotton is a strong and durable fabric, making it suitable for everyday wear.
- Undergarments undergo frequent washing and use, so strength and durability are essential qualities.
In conclusion, cotton is the most desirable fabric for making undergarments due to its absorbent nature, dull appearance, lack of shine, and strength. These qualities ensure comfort, privacy, and durability, making cotton the preferred choice for undergarments.

The fabric with a dull surface is Wool.
- Nylon: Nylon fabric has a smooth and shiny surface, giving it a lustrous appearance.
- Polyester: Polyester fabric also has a smooth and shiny surface, similar to nylon.
- Silk: Silk fabric is known for its smooth and luxurious appearance, with a natural sheen.
- Wool: Wool fabric has a dull surface, which means it lacks luster and shine. It has a soft and fuzzy texture.
Explanation:
- Fabric surfaces can vary in terms of their appearance and texture.
- Factors such as the type of fibers used and the weaving or knitting process contribute to the surface characteristics of a fabric.
- Wool, being a natural fiber, has a unique structure that gives it a matte or dull appearance.
- The surface of wool fabric is often described as soft, fuzzy, and non-reflective.
- This dull surface is one of the distinguishing features of wool, making it different from fabrics like nylon, polyester, and silk, which have a smooth and shiny appearance.
- Wool's dull surface is often desired for its natural and cozy aesthetic, making it a popular choice for winter clothing and home textiles.

Yes, silk is the most delicate type of material commonly used to make clothing. Unlike other materials such as cotton, which is much more forgiving when it comes to laundering and fabric care, silk is particularly susceptible to stains and damage from heat and light.

The natural fibres are obtained from:
Plants:
- Cotton: The most common natural fibre obtained from the cotton plant.
- Jute: Obtained from the stem of the jute plant.
- Flax: Derived from the stem of the flax plant and used to make linen.
- Hemp: Obtained from the hemp plant and used for various purposes including textile production.
Animals:
- Wool: Obtained from the fleece of sheep or other animals like goats, llamas, and rabbits.
- Silk: Produced by silkworms to make their cocoons. It is obtained by unwinding the silk thread from the cocoons.
Plants and animals both:
- Coir: Obtained from the outer husk of coconut.
- Cashmere: Obtained from the soft undercoat of cashmere goats.
- Mohair: Obtained from the hair of the Angora goat.
- Angora wool: Obtained from the Angora rabbit.
- Vicuna: Obtained from the Vicuña, a South American camelid.
Neither from plants nor animals:
- Asbestos: A mineral fibre, not obtained from plants or animals.
Summary:
Natural fibres can be obtained from various sources, including plants, animals, or both. Cotton, jute, flax, and hemp are examples of fibres obtained from plants, while wool and silk are obtained from animals. Some fibres, such as coir, cashmere, mohair, angora wool, and vicuna, can be derived from both plants and animals. However, asbestos is a mineral fibre and not obtained from either plants or animals.

These artificially manufactured fibres were made from polymers obtained from petrochemicals. These fibres are called synthetic or artificial fibres. The two most common ones are nylon and polyester. Nylon is made from two chemicals, adipic acid (AA) and hexamethylenediamine (HMD).

Experiment to test dye fixation on a 100% cotton-woven fabric:
To conduct an experiment to test dye fixation on a 100% cotton-woven fabric, the following properties can be examined:
1. Easily washable:
- This property refers to the ability of the fabric to retain its color after multiple washes.
- The experiment can involve subjecting the fabric to a series of wash cycles and evaluating the colorfastness of the dye.
2. Water repellence:
- This property refers to the fabric's resistance to the penetration of water.
- Since the experiment focuses on dye fixation, water repellence may not be directly relevant to the dyeing process.
3. Abrasion resistance:
- This property refers to the fabric's ability to withstand wear and tear caused by rubbing or friction.
- The experiment can involve subjecting the fabric to abrasion tests to assess the durability of the dye.
4. Moisture absorption:
- This property refers to the fabric's ability to absorb and hold moisture.
- While relevant to the overall performance of the fabric, it may not be directly related to the dye fixation process.
Conclusion:
Based on the properties mentioned, the most suitable choice for an experiment testing dye fixation on a 100% cotton-woven fabric is "Easily washable" (Option A). This property directly relates to the ability of the fabric to retain its color after washing, which is crucial in assessing the dye fixation process.

• Yak (Option A) produces a type of wool, known as yak wool, which is used for making textiles.
• Camel (Option B) also produces a type of wool, known as camel hair, which is used in making warm clothing and blankets.
• Goat (Option C) produces cashmere and mohair wool, both of which are highly prized for their softness and warmth.
• Woolly dog (Option D) does not produce wool suitable for textile use. Although some dogs have thick fur, it is not used for making woolen products.

Thus, the correct answer is D: Woolly dog.

• Sericulture refers to the process of breeding and rearing silkworms for the production of silk.
• Horticulture (Option B) involves the cultivation of plants, fruits, vegetables, and flowers.
• Agriculture (Option C) refers to the broader practice of farming, which includes the cultivation of crops and the rearing of animals.
• Aqua-culture (Option D) involves the cultivation of aquatic organisms, such as fish, shellfish, and plants, in water.

Thus, the correct term for the rearing of silkworms to obtain silk is Sericulture.

Cotton fibres are obtained from the fruits of cotton plants. The fruits of the cotton plant (cotton bolls) are about the size of a lemon. After maturing, the bolls burst open and the seeds covered with cotton fibres can be seen.

• Silk fiber is primarily made of protein, specifically a protein called fibroin, which is secreted by the silk glands of the silk moth. The protein fibers are then spun by the larvae (silkworms) to create silk threads.
• Carbohydrates (Option A), fats (Option B), and sugars (Option D) are not the primary components of silk.

• Hint:
  • The species of silkworm found in Assam predominantly feed on these plants.
  • Chewing of beans of the second variety of plants can be fatal.
  • Species of silkworms have been classified based on their feeding habit on the third variety of trees.
• Silkworms feed on some, castor, and mulberry leaves.
  • There are a variety of species of silkworms that feed on the leaves of different types of plants.
  • The silkworms that feed on mulberry leaves are called mulberry silkworms.
  • While non-mulberry silkworms survive on other plants like castor, som, oak, juniper, pine, etc.
  • Hence, leaving mulberry all other varieties of silks are called non-mulberry silks.

The jute fiber comes from the stem and ribbon (outer skin) of the jute plant. The fibers are first extracted by retting. The retting process consists of bundling jute stems together and immersing them in slow running water.

A staple is the fiber of cotton, wool or ramie etc of no more than a few inches long. A filament is usually a man-made fiber of indefinite length. All fabrics woven, knitted or crocheted are made from yarn.

Jute is a natural fiber that is commonly used to make products such as bags, ropes, and textiles. It has several properties that make it a popular choice for these applications. However, one of the properties listed is not associated with jute. Let's examine each property to determine which one does not belong:
A: Biodegradability: Jute is biodegradable, meaning it can be broken down by natural processes and does not contribute to environmental pollution.
B: Durability: Jute is known for its durability and strength, making it suitable for heavy-duty applications.
C: Smoothness: This property does not apply to jute. In its natural state, jute fibers have a rough texture and are not inherently smooth.
D: Strength: Jute is a strong fiber that can withstand considerable tension and pressure.
Based on the above analysis, the property that does not belong to jute is Smoothness (option C).

To determine which material traps the most air, we need to understand the properties of each material and how they interact with air.
Nylon:

• Nylon is a synthetic material that is lightweight and has good breathability.
• While it can provide insulation, it may not trap as much air compared to other materials.

Cotton:

• Cotton is a natural material that is breathable and comfortable to wear.
• It can hold some air within its fibers, providing a certain level of insulation.

Wool:

• Wool is a natural material known for its excellent insulation properties.
• The fibers of wool have a crimped structure, which creates air pockets, making it an effective insulator.
• Wool can trap a significant amount of air, providing warmth in cold conditions.

Polyester:

• Polyester is a synthetic material that is often used for insulation in various products.
• It can trap air within its fibers, providing insulation and warmth.

Conclusion:
From the given options, wool is likely to trap the most air due to its unique structure and insulation properties. It has a crimped fiber structure that creates air pockets, making it an effective insulator. Cotton and polyester can also hold some air within their fibers, but wool is generally considered to be the best material for trapping air and providing insulation. Nylon, on the other hand, may not trap as much air compared to the other materials mentioned.

Let's analyze each statement:

Ananya: Silk doesn't need to be detangled like wool because silk is obtained directly as thread from cocoon.

• Silk is obtained from the cocoon of silkworms, but it still needs to be processed to obtain the silk thread. The cocoon is boiled to kill the silkworm and loosen the silk thread, which is then carefully unwound from the cocoon. So, Ananya's statement is incorrect.

Ranchit: Silk doesn't need to be detangled like wool because thread from a single cocoon can be used as yarn directly.

• While it is true that silk thread can be directly used as yarn, it doesn't mean that it doesn't need to be detangled. Silk threads can still get tangled during the processing and weaving stages. So, Ranchit's statement is also incorrect.

Sanchit: Silk doesn't need to be detangled like wool because silk fibre is stronger than wool.

• Sanchit's statement is unrelated to the question. Strength of the fiber doesn't determine if it needs to be detangled or not. So, Sanchit's statement is incorrect.

Soni: Ananya and Ranchit are correct.

• As we discussed earlier, both Ananya and Ranchit's statements are incorrect. So, Soni's statement is incorrect as well.

Therefore, none of them are correct in this scenario.

 

Sheep Fleece:

• Sheep fleece refers to the wool that is obtained from the sheep's body, particularly the coat of wool that covers the sheep's skin.
• Fleece is made up of fibers that are densely packed together, providing warmth and insulation to the sheep.

Usability of Sheep's Fleece: Not all the fleece from a sheep can be used to make wool. There are several factors that determine the usability of the fleece:

• Quality: The quality of the fleece depends on factors such as fiber thickness, fineness, crimp, and uniformity.
• Cleanliness: Sheep can get dirty, and if their fleece is contaminated with dirt, grease, or other impurities, it may not be suitable for wool production.
• Health: The health of the sheep also plays a role. If a sheep is diseased or has poor nutrition, it can affect the quality of the fleece.

Different Types of Wool: Just like humans, sheep also have variations in the quality and thickness of their hair. This leads to different types of wool:

• Fine Wool: This comes from sheep breeds that have very fine and soft fibers. Examples are Merino and Rambouillet sheep.
• Medium Wool: This comes from sheep breeds with medium thickness fibers. Examples are Corriedale and Columbia sheep.
• Coarse Wool: This comes from sheep breeds with thicker and stronger fibers. Examples are Lincoln and Cotswold sheep.

Conclusion: While all the fleece from a sheep can technically be used, not all of it is suitable for making wool. The quality of the fleece, cleanliness, and the type of wool desired determine which parts of the fleece are suitable for wool production. Only the fleece that meets the desired quality standards and is free from impurities can be used to make wool.

Linen is a very strong fibre and slightly silky in appearance, due to the smooth, flat-surfaced nature of the phloem. Linen tends to be lint free, due to the length of the fibre. There are five stages between pulled up fibres and linen ready to be spun: Rippling, Retting, Breaking, Scutching and Hackling.

A filament is a fiber with an unlimited or seemingly infinite length. The long continuous filament fibers are measured in yards or meters. If a filament is bundled and cut it is called a tow. A fabric is created by fibers which have been spun into yarns and then bonded together.

Jute is a plant fiber, obtained from the stems of the jute plant Corchorus. It is long, soft, and shiny. Jute is spun into strong threads.
Whereas wool is obtained from animals like sheep, yak, etc.

Nylon is a man-made fiber.

Silk is obtained from Silkworms.

Therefore, the correct option is A.