Question

Find the weight of a lead pipe 3.5m long. The external diameter of the pipe is 2.4 cm and thickness of the pipe is 2mm. Given that 1cm³ of lead pipe weight 10 gm.

Answer 1

The external diameter of the lead pipe = 2.4 cm let the internal and external radius of the pipe be r and R respectively. therefore 2R=2.4 cm⇒ R=2.4/2=1.2 cm thickness of the pipe is 2 mm = 0.2 cm the internal radius r = 1.2-0.2= 1 cm the length of the lead pipe be h = 3.5 m = 3.5*100=350 cm. therefore the volume of the pipe = V= 22*50*0.44 = 484 cubic cm the weight of 1 cubic cm is 11 kg. thus the weight of the lead = 484*11 = 5324 kg