Q. Determine the correctness or otherwise of the following Assertion and Reason : Kevlar fibre has high strength and high modulus. : It has high orientation and low crystallinity. (A) Both and are true and is the correct reason for (B) Both and are true but is not the ...

Q. The correct combination of techniques to determine the crystallinity in fibres is (A) TGA and DSC (B) Birefringence and DSC (C) X-ray diffraction and Density measurement (D) Birefringence and X-ray diffraction Ans: X-ray diffraction and Density measurement

Q. One of the points which lies on the solution curve of the following differential equation 2𝑥𝑦 𝑑𝑥 + (𝑥2 + 𝑦2) 𝑑𝑦 = 0 with the initial condition 𝑦(1) = 1 is              (A) (−1, 1)           (B) (0, 0)                  (C) (0, 1)                  (D) (2, 1) Ans: (-1, 1)

Q. A cellulosic fabric has been treated with boric acid to impart flame retardancy. The wet expression is 100%. The molecular weight of boric acid is 62 and the atomic mass of boron is 11. Assume that no chemical reaction takes place between boric acid and the fibre. If 2.2 % boron has been added ...

Q. A wool fabric is to be dyed with an acid dye to a shade of 4% on the weight of fabric (owf). The material to liquor ratio is 1:40 and the exhaustion is 100%. The concentration (gpl) of the dye in the initial dye bath is         . Ans: 1-1

Q. The 2.5% span length and uniformity ratio of a particular variety of cotton fibre are 30 mm and 45%, respectively. The 50% span length (mm) of the fibre (rounded off to 1 decimal place) is         . Ans: 13.0-14.0

Q. If the moisture content of a fibre is 10%, its moisture regain (%) (rounded off to 2 decimal places) is       . Ans: 11.00-11.20

Q. A square plain jammed fabric has yarns with circular cross-section. If the yarn diameter is 0.02 cm, then number of ends per cm (rounded off to 1 decimal place) is  . Ans: 24.0-34.0

Q. If the linear density (tex) of a yarn is doubled, then percentage increase in tightness factor of single jersey knitted fabric (rounded off to 1 decimal place) is     Ans: 40.0-43.0

Q. The ratio of yarn tensile modulus to fibre tensile modulus, where the surface fibres are inclined at a twist angle of 25°, (rounded off to 2 decimal places) is Ans: 0.81-0.83