The magnetic field produced by a current-carrying straight conductor is circular and concentric around the conductor. The direction of the magnetic field lines can be determined using the right-hand thumb rule: if the right-hand thumb points in the direction of the current, the curled fingers show the direction of the magnetic field.
In the diagram above, the magnetic field lines are shown as concentric circles around the conductor, with the direction of current marked. The direction of the magnetic field is shown using arrows around the conductor.
Consider the following statements:
A. The junction area of a solar cell is made very narrow compared to a photodiode.
B. Solar cells are not connected with any external bias.
C. LED is made of lightly doped p-n junction.
D. Increase of forward current results in a continuous increase in LED light intensity.
E. LEDs have to be connected in forward bias for emission of light.