Question

iron pipe is 42 cm long and exterior radius 4 cm is 1 cm and iron veg hundred gram per centimetre cube find the weight of the pipe​

Answer 1

l=42 cm r=4 cm thickness=1 cm weight of iron=100g/cm

3

Volume of cylinder=πr

2

h

∴ Volume of iron pipe=π(4+1)

2

42−π×4

2

×42

=π×42(25−16)

=

7

22

×42×9=1188cm

3

Weight of 1 cm

3

iron=100g

∴ Weight of 1188 cm

3

iron=1188× 100=118800g=118.8kg