A fixed 14.4-cm-diameter wire coil is perpendicular to a magnetic field 0.65 T pointing up. In 0.20 s , the field is changed to 0.16 T pointing down. Part A What is the average induced emf in the coil?

Emf = 0.040 V

Explanation:

From Faraday's law of electromagnetic induction,

Emf induced = -N (dΦ/dt)

Φ = AB; (dΦ/dt) = A (dB/dt)

Emf induced = - NA (dB/dt)

Average emf induced = -NA (ΔB/Δt)

N = number of turns = 1

A = Area of the loop = πr² = π(0.072)² = 0.0163 m²

ΔB = 0.16 - 0.65 = - 0.49 T

Δt = 0.20 s

E = - (1)(0.0163)(-0.49)/(0.2)

E = 0.040 V

elly's long hair:

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c. if elly has some principles, and doesn't want to write a bad check, then now she has a problem.   her desire for the new hairstyle is in conflict with her honesty and integrity.

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justin can't pay the full balance:

a. he can't even handle the credit limit he has now.   under no circumstances should he ask for a higher limit.

b.   he can ask for the grace period to be extended.   but that's no solution, the bank will almost certainly refuse anyway, and there are much better options.   he knew the rules of his credit card when he started using it.

c.   he definitely should pay the interest on the balance, plus as much of the balance as he can cover at the same time.

d.   he definitely should pay the minimum otherwise they could shut down his card.   he should also pay as much more as he possibly can.   he should also remember the awkward situation he's in, stop buying stuff on credit that he can't afford, and avoid adding any more debt.

i'd say that justin's best best option isn't on this list of choices.   what he has to do:   pay as much as he can at least the minimum payment plus as much more as he can and then avoid adding more debt.

the answer is f1 and d2 because if you put equal force on those two points the beam would balance trust me on this