Final answer:
The magnetic field strength is greater inside a loop due to the concentration and unification of magnetic field lines, compared to the dispersed field around a straight wire.
Step-by-step explanation:
The magnetic field strength is greater inside a current-carrying loop of wire compared to a straight section of wire because of the nature of magnetic field lines and their density within the loop. In a straight wire, the magnetic field lines are concentric circles radiating outwards, with their strength inversely proportional to the distance from the wire. When the wire is looped, these lines are concentrated inside the loop, enhancing the magnetic field strength at the center and within the loop. The magnetic field is also much more uniform inside the loop or a solenoid, looking similar to that of a bar magnet. This can be deduced using the right-hand rule (RHR-2), Biot-Savart law, and the practical implications observed, such as in Oersted's experiment.