An electric motor best makes use of the fact that on a current-carrying wire in a magnetic field there exists which of these?. A) electromagnetic energy to be tapped.B) rotation.C) All of these.D) a force.E) a changing voltage.
I say it is roation or all of these
Indeed, the correct answer is option C) All of these. An electric motor makes use of multiple effects in a current-carrying wire in a magnetic field. Let's go through each of the choices to understand how they relate to an electric motor.
A) Electromagnetic energy to be tapped: An electric motor converts electrical energy into mechanical energy. It does this by utilizing the electromagnetic energy present in the current-carrying wire. When a current flows through the wire in a magnetic field, electromagnetic energy is present and can be tapped to perform work.
B) Rotation: One of the primary functions of an electric motor is to produce rotational motion. This is achieved by utilizing the force exerted on the current-carrying wire due to the interaction between the magnetic field and the current. This force causes the wire to rotate, resulting in the desired mechanical output.
D) A force: As mentioned earlier, the interaction between the magnetic field and the current-carrying wire leads to the generation of a force. This force is essential for the motor to produce motion and perform useful work.
E) A changing voltage: In an electric motor, a changing voltage is not a direct consequence of a current-carrying wire in a magnetic field. Instead, the motor itself may generate a changing voltage as a byproduct of its operation. This is more relevant for a generator, where mechanical energy is converted into electrical energy.
Considering the above explanations, the best answer is indeed option C) All of these, as an electric motor utilizes electromagnetic energy, causes rotation, generates a force, and may produce a changing voltage.