If a solid metal sphere and a hollow metal sphere of equal diameters are each given the same charge, the electric field (E) midway between the center and the surface is...A. greater for the solid sphere than for the hollow sphere. B. greater for the hollow sphere than for the solid sphere. C. zero for bothD. equal in magnitude for both, but one is opposite in direction from the other.

C. zero for both

Explanation:

In case of solid metal sphere , when it is given any charge , all the charges are transferred on the surface and within surface no charge exists . In case of hollow metal sphere , all charges reside on surface . In this way , in both solid and hollow sphere , all charge reside on the surface and no charge resides inside it . Hence due to absence of any charge inside  , there is no electric field inside the sphere in both the cases .  

Hence in both the case electric field is zero .

option C is correct .

radiation

explanation:

heat is transmitted by radiation