Does electric field depend on test charge?
The strength of the electric field depends on the source charge, not on the test charge. Because an electric field has both magnitude and direction, the direction of the force on a positive charge is chosen arbitrarily as the direction of the electric field.
Why test charge has no electric field?
But the test charge itself will produce its own field and interact with the existing field. So what you get to measure is the resultant field and not the original field. In order to make the difference between both the fields negligible, we take a test charge as small as possible.
Can electric field exist without current?
Without current there is no magnetic field and without voltage – no electric field. Under static conditions, either can exist w/o the other. A superconducting loop w/ a steady dc current has magnetic field, but no electric field.
Does test charge exist?
The existence of an electric field is a property of the source charge. The presence of the test charge is not necessary for the field to exist. The test charge serves as a detector of the field. The direction of is that of the force on a positive test charge.
Why do we need the electric field?
Electric fields provide us with the pushing force we need to induce current flow. An electric field in a circuit is like an electron pump: a large source of negative charges that can propel electrons, which will flow through the circuit towards the positive lump of charges.
Is the electric field real?
Incidentally, electric fields have a real physical existence, and are not just theoretical constructs invented by physicists to get around the problem of the transmission of electrostatic forces through vacuums.
Does electric field exist?
Do electric fields exist?
Can electric field create charge?
Coulomb is the unit of charge. Charges create electric fields, and the electric field created by one charge will cause other charges nearby to feel a force: opposite charges attract, and similar charges repel. An electric field is the electric force per unit charge.