wiz-icon
MyQuestionIcon
MyQuestionIcon
9
You visited us 9 times! Enjoying our articles? Unlock Full Access!
Question

A solid sphere A of mass m rolls without slipping on an inclined plane of inclination 30. Coefficient of friction between the inclined plane and the sphere is μ. Then, which of the following options is satisfied when the sphere undergoes pure rolling motion?

A
μ237
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
μ273
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
μ<237
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
μ<273
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B μ273
Le us assume the radius of the sphere is R.
F.B.D from the data given in the question is shown below.


From the diagram, we can deduce that
Fx=max [Net Force along x - direction]
mgsinθf=ma ......(1)
Fy=may [Net Force along y - direction]
N=mgcosθ .....(2)
Torque experienced by the sphere due to frictional force is given by
fR=Iα
where I= Moment of inertia of solid sphere =25mR2
fR=(25mR2)(aR) [α=aR]
f=25ma ......(3)
Substituting (3) in (1),
mgsinθ25ma=ma
gsinθ=(a+25a)
gsinθ=75a
a=57gsinθ
and from (3), we can say that
f=27mgsinθ .....(4)
For pure rolling, μNf
From (2) and (4)
μmgcosθ27mgsinθ
μ27tan θ
μ27tan 30
μ273
Hence, option (b) is the correct answer.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
Join BYJU'S Learning Program
CrossIcon