A battery of e.m.f 3.0V is connected across a potentiometer wire AB of length 10\(\Omega m^{-1}\) as illustrated in the diagram above. If the jockey J makes contact at the 30cm mark, determine the resistance of length AJ and voltage across AJ.
A. 3.0\(\Omega\); 0.9V B. 3.0\(\Omega\); 3.0V C. 3.3\(\Omega\); 0.3V D. 3.3\(\Omega\); 9.0V
