Calculate the magnitude of the electric field inside the solid at a distance of 9.50 cm from the center of the cavity. Express your answer using two significant figures.

Question:

A point charge of -2.14uC  is located in the center of a spherical cavity of radius 6.55cm  inside an insulating spherical charged solid. The charge density in the solid is 7.35×10−4 C/m^3.

a) Calculate the magnitude of the electric field inside the solid at a distance of 9.50cm  from the center of the cavity.  

Express your answer using two significant figures.

The magnitude of the electric field inside the solid at a distance of 9.50cm from the center of the cavity

Explanation:

A point charge ,q = is located in the center of a spherical cavity of radius ,  m inside an insulating spherical charged solid.  

The charge density in the solid , d =

Distance from the center of the cavity,R =

Volume of shell of charge= V  =

Charge on the shell ,Q =

Electric field at m due to shell

E1 =  

Electric field at   due to 'q' at center

E2 =

The magnitude of the electric field inside the solid at a distance of 9.50cm from the center of the cavity

= E2- E1

i think it would be 5