The magnetic field of a cylindrical magnet that has a pole-face diameter of 3.3 cm can be varied sinusoidally between 29.6 t and 30.0 t at a frequency of 17 hz. (the current in a wire wrapped around a permanent magnet is varied to give this variation in the net field.) at a radial distance of 2.5 cm, what is the amplitude of the electric field induced by the variation

As we know that induced EMF is given by rate of change in magnetic flux

so here we can say

here we know that

so here we can say

now by relation of EMF and electric field we can say

now plug in all values

r = 2.5 cm

f = 17 Hz

so electric field is given as E = 0.085 N/C

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day