An observer that movean observer that moves with an electrical charge senses: s with an electrical charge senses:
a magnetic field
an electric field
electric and magnetic fields
no field

the device is called “ rocket engine”

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )

i believe the answer is a hope it and is correct