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

A large conducting sphere of radius r, having a charge Q is placed in contact with a small neutral conducting sphere of radius r′ and is then separated. The charge on smaller sphere will now be:

A
Q(r+r)r
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
Q(rr)r
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
Qrr+r
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
Qrr+r
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution

The correct option is D Qrr+r
Charges will be redistributed when both spheres are placed in contact with each other, such that common potential is achieved.

Charges are distributed in ratio of capacitance. Let Q1 and Q2 be the charges of bigger and smaller spheres, respectively.

V1=V2

Q1C1=Q2C2

Q1Q2=C1C2=rr (C=4πϵ0r)

Q1Q2+1=rr+1

Q1+Q2Q2=r+rr ......(1)

From conservation of charge on system of two spheres,

Q1+Q2=Q+0=Q ........(2)

From eqs.(1) and (2)

QQ2=r+rr

Q2=Qrr+r

Hence, option (d) is correct.

flag
Suggest Corrections
thumbs-up
3
Join BYJU'S Learning Program
Join BYJU'S Learning Program
CrossIcon