# GATE (TF) Textile 2008 Question Paper Solution | GATE/2008/TF/81

A precision winder has to wind 4 kg of yarn of 40 tex

###### Question 81 (Textile Engineering & Fibre Science)

If the efficiency of the machines is 91% additional time (min) required to do the same job is approximately

Option B is correct.
Given in the question-

Winding machine speed=800 m/min

Yarn weight to be wind=4 kg
=4000 gm

Yarn tex=40 tex

Time taken for winding(min)=?

By unitary rule-

1000 m length have=40 gm weight

i.e.

40 gm weight has=1000 meter length

1 gm ………………….=1000/40

Then, 4000 gm has…………=1000 x 4000/40

Total length to be wind=100000 meter

Time taken for winding(min)=Total length to be wind/Winding machine speed

Time taken for winding(min)=100000/800

Time taken for winding(min)=125

This time ,when 100% efficiency is there.

Now, machine gives 91% efficiency.

Winding speed=800 x 91%

Winding speed=800 x 91/100

Winding speed= 728 m/min

Now,

Time taken 2=Winding length/winding speed

Time taken 2=100000/728

Time taken 2=137.4 min

Additional time required to do the same job=Time taken 2 for winding-Time taken for winding

Additional time required to do the same job=137.4-125

Additional time required to do the same job=12.4 min
=12 min (Ans)