A 15 kg mass, tied to the end of a 0.5 m long steel wire, is whirled in a vertical circle. The cross- section of the wire is 0.02 cm2. When the mass is at the bottom of the circle, its angular velocity is 2 rev s i. Find the elongation of the wire at this point.

Question

A 15 kg mass,  tied to the end of a 0.5 m long steel wire,  is whirled in a vertical circle.  The cross-  section of the wire is 0.02 cm2.  When the mass is at the bottom of the circle,  its angular velocity is 2 rev s i.  Find the elongation of the wire at this point.

Elena · Answer

Y=2•10¹¹ Pa ω=2πf =2π•2=4π rad/s. ma=T-mg m ω²R =T – mg T=m(ω²R+g) =m(16π²R +g)=… T/A =Y•ΔL/L ΔL=TL/AY =…