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

A uniform disc of radius 5.0 cm and mass 200 g is fixed at its centre to a metal wire, the other end of which is fixed to a ceiling. The hanging disc is rotated about the wire through an angle and is released. If the disc makes torsional oscillations with time period 0.20 s. The torsional constant of the wire is :

A
0.25kg m2/s2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
0.5kg m2/s2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
25kg m2/s2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
2.5kg m2/s2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A 0.25kg m2/s2

The situation is shown in figure The moment of inertia of the disc about the wire is
I=mr22=(0.200kg)(5.0×102m)22=2.5×104kgm2
The time period is given by
T=2πICorC
=4π2IT2=4π2(2.5×104kgm2)(0.20s)2
=0.25kg m2/s2

834965_296400_ans_d6e81fe5f2b6486a94b053f749e9a063.png

flag
Suggest Corrections
thumbs-up
0
similar_icon
Similar questions
View More
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Expression for SHM
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon