PHYS 102 – Chapter 31 – Review Problems
- A single-turn plane loop of wire of cross sectional
area 40 cm2 is perpendicular to a magnetic field that increases
uniformly in magnitude from 0.5 T to 5.5 T in 2.0 seconds. What is the
resistance of the wire if the induced current is 1.0 mA?
- A rectangular loop of wire is placed midway between
two long straight parallel conductors as shown in figure 1. The conductors
carry currents I1 and I2 as indicated.
If I1 is increasing and I2 is
constant, what is the direction of the induced current in the loop?
- A magnet is taken towards a metallic ring in such a
way that a constant current of 0.01 A is induced in it. The total
resistance of the ring is 0.25 W.
In 10 seconds, by how much does the flux of the magnetic field through the
- Consider a circular loop of wire within which, the
magnetic flux, FB,
is given as a function of time as: FB
= a t2 + b ,
where a and b are constants. If the induced emf is 48 V at t
= 3 s, what is the value of a?
- A 2.0-T uniform magnetic field makes an angle of 60o
with the xy plane. What is the magnetic flux through an area of 3-m2
portion of the xy plane?
- Figure 2 shows a conducting bar moving with a
constant speed of 5.0 m/s to the right. Assume that R = 5.0 W, L = 0.20 m, and that a uniform
magnetic field of 3.5 T is directed into the page. Calculate the magnitude
of the applied force pulling the bar.