Answer:
331.75 V
Explanation:
Given:
Number of turns of the coil, N = 40 turns
Area, A = 0.06 m²
Magnetic Field, B = 0.4 T
Frequency, f = 55 Hz
Maximum induce emf, E₀ = NABω
but ω = 2πf
Maximum induce emf, E₀ = NAB(2πf₀)
Maximum induce emf, E₀ = 2πNABf₀
Where;
N is number of turns of the coil
A is area
B is magnetic field
ω is the angular velocity
f is the frequency
E₀ = 2 × π × 40 × 0.06 × 0.4 × 55
E₀ = 342.81 V
The maximum induced emf is 331.75 V
It does produce 'sound' ... a compression wave traveling through the air. But your ears don't hear a sound that's vibrating less than 20 or 30 times every second. If you could swing your pendulum that fast, you could hear the sound of its vibrations pushing the air around.
The answer is B. This form of magnesium chloride is not a liquid but a solid that is white and colorless.