Explanation:
Given that,
Charge acting on the object,
Force acting on the object, (in downward direction)
(a) The electric force acting in the electric field is given by :
E is the electric field
E = 4.75 N/C
The direction of electric field is as same as electric force. But it is negative charge. So, the direction of electric field is in upward direction.
(b) The charge on the proton is,
The force acting on the proton is :
If the charge on the proton is positive, the force on the proton is in upward direction.
Hence, this is the required solution.