Mary wants to investigate the relationship between magnetism and the movement of an electrical charge. She has a coil of wire hooked to an ammeter to measure current. She has a moveable magnet inside the coil. As she moves the magnet within the coil, the ammeter indicates a certain current. Mary wants to increase the amount of current from the device. Which action would be the BEST to increase the current and why?
A Use a differently shaped magnet, because it would increase the magnetic field.
B Increase the diameter of coil, because more of the magnetic field will be included.
C Reduce the number of coils because this would increase the effect of the magnetic field.
D Move the magnet faster within the coil, because this will increase the rate of change of the magnetic field.