MATH'S PRESENTATION

conversions

ALINA AFZAL

Slides prepared by :Alina Afzal

INDIRECT SYSTEMCount

Thickness

Higher the count lower the thickness.

In indirect system c=l/w (Length per unit mass)

DIRECT SYSTEM Count

Thickness

Thicker the yarn higher the count.

In direct system c=w/l (mass per unit length)

INTRA CONVERSIONS & INTER CONVERSIONS

Inter - ( from outside )

direct – indirect relation .

o Intra – (with in)

o Direct-direct relation.o Or o Indirect – indirect relation.

CONVERSIONSWhat are conversions ?

 

Conversions:

A change in the form of a measurement, different units, without a change in the size

or amount.

Count : The thickness and thinness of yarn is called count .

Length: Distance. How far from end to end.

example: the length of this guitar is about 1 meter

Weight: "Heaviness". The downward force caused by gravity on an object.

• Problem # 1 (English cotton count sys)

• If 240 yards of cotton yarn weigh 40 grains ,what is the count of the yarn?

• C = (length in length units) / (wt in wt unit) • C = (240 yards / 1 hank =840 yards) / (40 grains / 1 lbs =7000grains)

• C = [240 / 840] / [40 /7000] = 50s

• Problem # 2• Find the count of 960 m of cotton yarn which

weigh 20 gm.(Use French Cotton system)• Since French Cotton system is also indirect

sys so formula will be • C= Length in length unit/Wt in wt

unit=(960m/1km)/(20 gm/0.5kg)=(960/1000)/(20/500)=23.75=24’s

Problem # 3 (1lb ,cut of 300 yds) What is the wt of 18 yds of woolen yarn

whose count 21’s(American cut) Wt=(18/300)/(21/1)=(18/300).

(1/21)=(0.0028571429)lbs(7000)=20 grains