Asquare loop of side length a =2.9 cm is placed a distance b = 1.2 cm from a long wire carrying a current that varies with time at a constant rate, i. e. i(t) = qt, where q = 2.3 a/s is a constant. show answer correct answer 25% part (a) find an expression for the magnetic field due to the wire as a function of time t at a distance r from the wire, in terms of a, b, q, t, r, and fundamental constants. b(t) = ( μ0 q t )/( 2 π r ) part (b) what is the magnitude of the flux through the loop? select the correct expression. part (c) if the loop has a resistance of 2.5 ω, how much induced current flows in the loop?

Explanation:

Magnetic field due to a long wire

B =  (  μ₀ / 4π ) x 2 I / r  ( I is current through the wire )

= (μ₀ Q t ) / ( 2 π r )                    [ I = Q t ]

b )  Magnetic field will change through the length of the square shaped loop . So we shall have to take the help of integration to calculate the flux through the loop.

Flux Φ = ∫ B dA

=∫ (  μ₀ / 4π ) x 2 I / r  dA

10⁻⁷ x 2 I ∫ a dr/r

2 x 10⁻⁷ x Qt x a [ ln (2.9+1.2) / 1.2  ]

4.6 x 10⁻⁷ x 2.9 x 10⁻² t  ln 4.1 / 1.2

16.4  x 10⁻⁹ t

Φ( t ) =  16.4 x 10⁻⁹ t

Induced emf  = dΦ( t ) / dt = 16.4 x 10⁻⁹ v

current

16.4 x 10⁻⁹  / 2.5

= 6.56 x 10⁻⁹

elly's long hair:

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b. if she has overdraft protection, then there's no problem.   she can go ahead and write a check that her account can't cover, then sometime later, pay the bank some outrageous usury for loaning her a few bucks for a few days, but with beautiful hair.

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.

d.   if the bank will not process a check she writes, then even if she had a million $$ in her account, she couldn't use any of it.   the amount she has in her account is not the problem.   and if i may suggest, she might as well close her checking account, and put the money where it'll work for her.   it's not doing her a bit of good in a checking account, since she can't write any checks.

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.

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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.

i would like to make dinner for my mom, dad, and sister