1) A rubber balloon has been inflated so that it is a sphere of radius a where a

Question

1) A rubber balloon has been inflated so that it is a sphere of radius a where a remains a constant. The balloon has charge Q uniformly spread over its outer surface. (Treat the balloon as a perfect sphere, ignoring the means by which air is introduced. Assume the air has no effect other than to change the size of the balloon.) a)what is the potential of the balloon’s outer surface? b) what is the potential at fixed point P1 a distance 2a from the center of the balloon c) what is the potential at fixed point P2 a distance 4a from the center of the balloon c) now the balloon is further inflated until its radius is 3a. (Its center remains in the same place and the charge Q remains the same.)Now what is the potential at (i) the balloon’s outer surface, (ii) point P1 and (iii) point P2

Explanation / Answer

Given

a Spherical ballon of radius a , charge Q

we know that the potential of a charged sphere at R so that R > a is  

V = kQ/R

a) potential at outer surface of the ballon at R=a is  

V = kQ/a

b) at R = 2a tha is at point P1 is  

V1 = kQ/2a

c) P2 at 4a distance from center

V2 = kQ/4a

now the radius of the ballon increased from a to 3a then

i) V = kQ/3a

ii) V1 = kq/(2*3a) = kQ/6a

iii) V2 = kQ/(4*3a) = kQ/12a

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.