Soru
An inductor is formed by winding N turns of a thin conducting wire into a circular loop of radius a . The inductor loop is in the x-y plane with its center at the origin and connected to a resistor R, as shown in Fig. 6-3. In the presence of a magnetic field B=B_(0)(hat (y)2+hat (z)3)sinomega t where a is the angular frequency, find (a) the magnetic flux linking a single turn of the inductor, (b) the transformer emf given that N=10, B_(0)=0.2T, a=10cm and omega =10^3rad/s (c) the polarity of V_(cmf)^tr at t=0 and (d) the induced current in the circuit for R=1kOmega (assume the wire resistance to be much smaller than R)
Çözüm
4.2
(181 Oylar)
Fikri
Profesyonel · 6 yıl öğretmeni
Uzman doğrulaması
Cevap
(a) The magnetic flux linking a single turn of the inductor is given by:
where
is the magnetic field strength,
is the area of the loop, and
is the angular frequency.(b) The transformer emf is given by:
Substituting the expression for
from part (a), we get:
(c) The polarity of
at
can be determined by substituting
into the expression for
from part (b). Since
is zero at
, the emf is also zero at that time. Therefore, the polarity of
at
is indeterminate.(d) The induced current in the circuit can be found using Ohm's law:
Substituting the expression for
from part (b), we get:
Substituting the given values, we get:
Simplifying further, we get:
Therefore, the induced current in the circuit is
A.