Q. A wet polyester fabric has areal density of 160 g/m2. The initial temperature of the wet fabric is 20°C. After it is completely dried on a cylinder dryer, its areal density drops to 100 g/m2. Consider, Specific heat of polyester as 2.0 J/g oC Specific heat of water as 4.2 J/g oC ...

Q. A polyester fabric is dyed with a disperse dye till equilibrium is reached. If the concentration of the dye in the spent dyebath is 0.05 gpl and the partition coefficient is 1000 ml/g, then amount of dye in the fibre (g/100 g) is      . Ans: 5-5

Q. A 180 denier polyester multifilament yarn, a 60 Ne cotton yarn and a 50 Nm (metric count) polyester/wool yarn are twisted together. The resultant linear density (tex) of the 3-ply yarn, neglecting twist contraction, (rounded off to 2 decimal places) is Ans: 49.50-50.00

Q. The 95% confidence limits of mean yarn tenacity (cN/tex) based on 100 test samples is 30 ± 1.5. The number of test samples required to obtain 95% confidence limits of 30 ± 0.5 is     . Ans: 900-900

Q. In a vibroscope, the fundamental resonant frequency of fibre X is twice that of fibre Y. Keeping the test length and tensioning weight the same, if the linear density of fibre Y is 10 denier, then the linear density (denier) of fibre X (rounded off to 1 decimal place) is Ans: 2.5-2.5

Q. A sample of 150 cotton fibres is tested for maturity. The number of normal and thin-walled fibres are 105 and 30, respectively. The rest are dead fibres. The maturity ratio is Ans: 1-1

Q. In a shuttle loom, if the loom speed (picks per minute) is increased by 20%, then the percentage increase in picking power required per meter of fabric is Ans: 41-45

Q. A yarn is passing through an additive type tensioner. The mass of dead weight on disc is 50 g and the coefficient of friction between yarn and disc is 0.3. If the input tension is 50 gf, then the output tension (gf) is . Ans: 79-81

Q. If the value of twist retraction of a yarn is 0.2, then the value of twist contraction (rounded off to 2 decimal places) is  Ans: 1.24-1.26

Q. The spindle speed of a ring frame, producing a yarn of 25 tex, is 25000 rpm and the rate of delivery is 25 m/min. The twist multiplier (m-1×tex0.5) of the yarn is Ans: 5000-5000