Answers

2016-02-22T18:47:17+05:30
Let the height of the original cylinder be h cm

diameter =2 cm

so the radius = 1 cm

Height of the new cylinder = 16 cm

diameter = 20 cm

so the radius = 20/2 =10 cm

this is a hollow cylinder whose thickness = 2.5 mm = 0.25 cm
so the radius of hollow cylinder = 10-2.25=9.75 cm

ATQ

volume of original cylinder = volume of the new cylinder

πr²h                    =     π(R² - r²) h
22/7 × 1² × h       =     22/7 ×(10²- 9.75²) ×16
1 × h                   =80.5 × 16
1h                      =1288 cm

so the height should be = 1288 cm
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