FREE Physics Electricity and Magnetism Questions and Answers
A 12 V battery is connected to a resistor with a resistance of 4 ohms. What is the current flowing through the circuit?
Correct!
Wrong!
Using Ohm’s Law, V=IR, rearrange to find current: I= V/r = 12V4Ω=3A.
If the current in a wire doubles, how does the magnetic field around the wire change?
Correct!
Wrong!
The magnetic field (B) around a current-carrying wire is directly proportional to the current (I), as described by Ampere’s Law: B∝I. If the current doubles, the magnetic field also doubles.
Two charges +2𝜇𝐶 and −3𝜇C are 0.1 m apart. What is the magnitude of the electrostatic force between them? (Use 𝑘=9×10'9 N\cdotpm'2/C2).
Correct!
Wrong!
The electrostatic force is given by Coulomb’s Law: F=k r 2∣q 1 q 2 ∣/r2 .
Which of the following is true about a series circuit?
Correct!
Wrong!
In a series circuit, resistances add directly: 𝑅total=𝑅1+𝑅2+⋯+𝑅𝑛.
A coil of wire is moved through a magnetic field, inducing a voltage. Which factor will NOT affect the magnitude of the induced voltage?
Correct!
Wrong!
According to Faraday’s Law of Electromagnetic Induction, the induced voltage depends on the rate of change of magnetic flux, the strength of the magnetic field, the number of coil turns, and the motion of the coil. Resistance affects the current, not the voltage.