wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

A circular tube of mean radius 8 cm and thickness 0.04 cm is melted up and recast into a solid rod of the same length. The ratio of the torsional rigidities of the circular tube and the solid rod is

A
(8.02)4(7.98)4(0.8)4
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
(8.02)2(7.98)2(0.8)2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
(0.8)2(8.02)4(7.98)4
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
(0.8)2(8.02)3(7.98)2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A (8.02)4(7.98)4(0.8)4
C1=πη(r42r41)2l,C2=πηr42l
Initial volume=Final volume
π[r22r21]lρ=πr2lρ
r2=r22r21r2=(r2+r1)(r2r1)
r2=(8.02+7.98)(8.027.98)
r2=16×0.04=0.64cmr=0.8cm
C1C2=r42r41r4=[8.02]4[7.98]4[0.8]4

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Order of Magnitude
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon