- #1

rudransh verma

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- Homework Statement
- An hollow nonconducting sphere/ shell with a inner radius of a=1.5 cm and outer radius of b=2.4 cm has a volume charge density of rho =A/r and at the center a ball charge of q=+75 fC.

What is the value of A if electric field inside the shell(a<=r<=b) is to be uniform ?

- Relevant Equations
- In the solution it is establishing a relationship between volume charge density and net charge on sphere.

delta q=rho deltaV

rho=dq/dV

dq=rho4pir^2dr

Then integrate dq from 0 to a because A is to be uniform in shell.

Ans: A= 5.3*10^-11 C/m^2

How do we approach these problems? Looking at the answer A seems to be surface charge density. What is A? What is the direction of uniform field E. I don’t think there will be any movement of charges because it’s non conductor.

rho=dq/dV

dq=rho4pir^2dr

Then integrate dq from 0 to a because A is to be uniform in shell.

Ans: A= 5.3*10^-11 C/m^2

How do we approach these problems? Looking at the answer A seems to be surface charge density. What is A? What is the direction of uniform field E. I don’t think there will be any movement of charges because it’s non conductor.