This is the key answers but I just dk the full solution

ACTIVITY 3: CHALLENGE PROBLEMS Directions: Solve the following problems. Show your complete solutions. Express your final answers in two decimal places. 1. A gold nucleus has a radius of 3 x 10'15 m and carries a charge of 799? (a) What is the potential at its surface? (b) How much energy would be required to bring a proton from a large distance up to the surface of the gold nucleus. 2. A point charge of - 5.0 nC is 2.0 m from point A and 5.0 m from point B. (a) Find the potential at point A and point B. (b) Calculate the potential difference between points A and B. 3. Equal charges of + 2.50 no are situated at the three corners of a square of sides 5.0 m. (a) Find the potential at the unoccupied corner. (b) Calculate the electric potential energy of a +2 uC charge placed at that corner. ACTIVITY 3: CHALLENGE PROBLEMS 1. (a) V = 3.79 x 107 V (b) 6.07 x 10-12 J 2. (a) VA = - 22.50 V; VB = - 9 V (b) VAB = 13.50 V 3. (a) V = 12. 18 V (b) U = 2.44 X 10-5 J