List of practice Questions

A block with a trapezoidal cross-section is placed over a block with a rectangular cross-section as shown above.
Which one of the following is the correct drawing of the view of the 3D object as viewed in the direction indicated by the arrow in the above figure?

The twist angle (degree) of surface fibres in a yarn with density of 700 kg/m\(^3\) and twist multiplier of 6000 m\(^{-1}\).tex\(^{0.5}\) (rounded off to nearest integer), is ________________.

In a multiplicative type tensioner, the angle of wrap is 90° and the coefficient of friction between the yarn and the guide is 0.2. If the input yarn tension is 10 cN, then the output yarn tension (cN) is (rounded off to 1 decimal place) ______________.

A take-up motion is shown below. The number of teeth on gear A, B, C, D and E are 60, 20, 40, 25 and 50, respectively. The circumference of the take-up roller is 40 cm. If one tooth is broken on gear B, then the wavelength (cm) of the fault in fabric (in integer) is ______________.

The tensile load (F) in Newton (N) and the elongation (e) in cm of a yarn are related as follows \[ F = 2e^2 + e \] If the breaking elongation of the yarn is 10 cm, then the work of rupture (N·m) of yarn (rounded off to 2 decimal places) is ________________.

Under steady-state thermal conditions, the temperature at various locations in a two-plate Togmeter is as shown in the Figure given below. If the thermal resistance of the standard bottom plate is 1.5 K/W, then the thermal resistance (K/W) of fabric specimen (correct up to 1 decimal place) is ________________.

For a wool fibre strand, the relationship between \( V_r \) (limit CV % of linear density) and \( N \) (average number of fibres in the cross-section of the strand) is given below. \[ V_r = \frac{112}{\sqrt{N}} \] For the above relationship, the CV % of linear density of wool fibre (rounded off to 2 decimal places) is ______________.

The breaking load of a cotton yarn, with a twist multiplier of 4 tpi·Ne\(^ {-0.5} \), is 2.5 N. If the twist (number of turns per inch) of yarn is 20, then the tenacity (cN/tex) of the yarn (rounded off to 2 decimal places) is ______________.

A cotton fabric is dyed at 5% shade (owf) using a monofunctional reactive dye. The molecular weight of the dye and cellobiose unit is 400 and 342, respectively. If all the hydroxyl groups in cellulose are accessible for reaction, the percentage of unreacted hydroxyl groups of cellulose remaining after dyeing (rounded off to 2 decimal places) is ________________.

The Gibb’s free energy equation for a system undergoing phase transition is given by \( \Delta G = \Delta H - T\Delta S \), where \( \Delta G \) is the change in Gibb’s free energy, \( \Delta H \) is the change in enthalpy, \( \Delta S \) is the change in entropy and \( T \) is the temperature in Kelvin.
During melting transition, two systems A and B, show no difference in \( \Delta H \) but B exhibits 10% lower \( \Delta S \). The ratio of melting temperature of B to that of A (rounded off to 2 decimal places) is ________________.

A monofilament gets extruded at a speed of 10 m/min from a spinneret of 0.2 mm diameter. In order to ensure a spin draw ratio of 11, the first godet roller with a diameter of 70 cm has to rotate with an angular velocity (rpm) of (rounded off to nearest integer) ______________.

Nine slivers having same mean linear density are doubled on a drawframe. If the standard deviation of linear density of each sliver is 0.3 ktex, then the standard deviation (ktex) of linear density of the doubled sliver (correct up to 1 decimal place) is ________________.

Consider the following statements with reference to testing of cotton fibre in HVI: P. Strength is measured in single fibre form
Q. Strength is measured in fibre bundle form
R. Fineness is measured by air flow method
S. Fineness is determined by measuring fibre diameter The combination of TRUE statements is:

Determine the correctness or otherwise of the following Assertion [a] and Reason [r].
[a]: In crease resistant finishing process of cotton with DMDHEU, curing is not carried out in steam.
[r]: Steam causes DMDHEU to self-polymerise rather than crosslink cotton.

Consider the following statements with respect to a cotton fabric which has been fully desized and bleached but not scoured:
P. It has residual seed coat fragments
Q. It has poor water absorbency
R. It has high whiteness index
S. It has high crease recovery
The combination of TRUE statements is:

In a dye identification test, a dyed fabric is immersed in an aqueous alkaline solution of a reducing agent. The colour of the dyed fabric changes and some dye bleeds out in the solution. The correct combination of the fabric and dye is:

Assuming the step size \( h = 1 \), the numeric value (rounded off to 2 decimal places) of the definite integral
\[ \int_1^3 \frac{x}{1+x} \, dx \] obtained using Simpson’s rule is ________________.

Let \( y' \) and \( y'' \) denote the first and second derivatives of \( y \). Let \( y(x) \) satisfy:
\[ y'' - 3y' + 2y = 0,\quad y(0)=1,\quad y'(0)=3. \]
Then \(y''(0)\) (in integer) is ____________.

Keeping the speed of all other components of a carding machine unchanged, the angular velocity of a cylinder with damaged wire points in an area of 2 cm \( \times \) 2 cm is doubled. Wavelength of the periodic fault in the card sliver would be:

Determine the correctness or otherwise of the following Assertion [a] and Reason [r].
[a]: As compared to parallel wound yarn packages, ring bobbins exhibit lower tendency of slough off during unwinding.
[r]: The main winding layers in the ring bobbins are separated by cross-winding layers.

A set of yarns is produced with the same linear density. If these yarns follow a helical model and their diameter is inversely proportional to twist (turns per unit length), then the yarns have the same:

Consider the following statements for a shuttle loom having linear (straight line) displacement profile for the picker:
P. The maximum actual acceleration of shuttle depends on loom speed and alacrity of picking system
Q. The maximum actual velocity of shuttle depends on loom speed
R. The maximum actual acceleration and maximum actual velocity of shuttle occur at the same time
S. Nominal displacement of shuttle is inversely proportional to the angular movement of crank shaft
The combination of TRUE statements is:

Eight-end regular sateen fabric can be woven with move (step) numbers of:

Consider the following components of a needle:
P. Shank
Q. Beard
R. Barb
S. Latch
The combination of correct components of a needle in a needle punching nonwoven machine is

The schematic of elastic recovery of a textile material is given below.

Where:
AB = original length; BD = total extension; CD = elastic extension; BC = permanent set.
With reference to the above schematic, consider the following statements:
P. For perfectly elastic material, BC = 0
Q. For perfectly elastic material, CD = 0
R. For perfectly plastic material, BC = 0
S. For perfectly plastic material, CD = 0
The combination of TRUE statements is: