Radio astronomers detect electromagnetic radiation at 45.0 MHz from an interstellar gas cloud. They suspect this radiation is emitted by electrons spiraling in a magnetic field. (me=9.11×10-31 kg, e-=1.60×10-19C) What is the magnetic field strength inside the gas cloud?

a) What current is needed to generate the magnetic field strength of 10 T at a point 1.2 cm from a long, straight wire? (

What value of resistor R gives the circuit in the figure above a time constant of 27

What is the electric field amplitude of an electromagnetic wave whose magnetic field amplitude is 1.80 mT?

Field of a circular loop: Two coaxial circular coils of radius R = 15 cm, each carrying 4.0 A in the same direction, are positioned a distance d = 20 cm apart, as shown in the figure. Calculate the magnitude of the magnetic field halfway between the coils along the line connecting their centers. (μ0 = 4π × 10-7 T ∙ m/A)

A 10 cm x 10 cm square is bent at a 90 angle. A uniform 7.0×10−2 T magnetic field points downward at a 45

A series RLC circuit attached to a 120 V/60 Hz power line draws 1.80 A of current with a power factor of 0.940. What is the value of the resistor?

The magnetic field in the figure is decreasing at the rate 0.55 T/s.  (e = 1.60 x10-19 C, mproton = 1.67×10-27 kg) a) What is the magnitude of the acceleration of a proton at rest at point a? What is the direction of acceleration of point a? b) What is the magnitude of the acceleration of a proton at rest at point d? What is the direction of acceleration of point d?

A 19.0 mH inductor is connected across an AC generator that produces a peak voltage of 10.5 V.  a) What is the peak current through the inductor if the emf frequency is 100 Hz? (3 points)   b) What is the peak current through the inductor if the emf frequency is 100 kHz? (3 points)

A 3.0 mH inductor is connected in parallel with a variable capacitor. The capacitor can be varied from 100 pF to 400 pF. a) What is the minimum oscillation frequency for this circuit? (2 points) b) What is the maximum oscillation frequency for this circuit?  (2 points)