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All 9 questions. After you submit, each question shows the right answer and why. Back to the quick check
If you snap a bar magnet in half, you get one piece that is only a north pole and one piece that is only a south pole.
You push the north pole of one magnet towards the north pole of another. What happens?
An electric current flowing in a wire can make a nearby compass needle move.
Why does the north end of a compass needle point towards the geographic North Pole?
A proton (charge 1.6 × 10⁻¹⁹ C) moves at 1.0 × 10⁶ m/s at right angles to a 0.50 T magnetic field. What is the magnetic force on it, in units of 10⁻¹⁴ N?
A magnetic field can change the direction of a moving charged particle without changing its speed.
The magnetic flux through each turn of a 100-turn coil falls steadily by 2.0 × 10⁻³ Wb in 0.10 s. What is the size of the induced emf, in volts?
Taking μ₀ = 1.2566 × 10⁻⁶ N A⁻², what is the magnetic field 5.0 cm from a long straight wire carrying 10 A? Give your answer in microtesla (μT).
Explain why the minus sign in Faraday's law (Lenz's law) is required by conservation of energy, and why a static magnetic field can deflect but never accelerate a free charge.
