If a circular piece of tin has a measured radius of 2.6cm, then what is its circumference?

If a circular piece of tin has a measured radius of 2.6cm, then what i

1.	If a circular piece of tin has a measured radius of 2.6cm, then what is its circumference?
Answer» Solution :r= 2.6cm Circumference of circular disc= `2pi r` `=2 xx 3.1428 xx 2.6` Here 2.6 has only 2 significant DIGITS. HENCE in the above MULTIPLICATION `pi` value should be written with `2 + 1= 3` significant figures. `pi= 3.1428= 3.14` Circumference `=2 xx 3.14 xx 2.6` = 16.328 This is to be rounded off to 2 significant digits. Circumference is 16cm.