An induced emf will occur if A. the strength of the magnetic field is changed. B. the coil's area is changed. O C. the angle at which the magnetic field and the coil's area meet is changed. D. all of the above.

The horizontal wire can be levitated-held up against the force of gravity-if the current in the wire is A. Right to left. B. Left to right. C. It can't be done with this magnetic field. X FG

A. 0.0155 T/s B. 0.0996 T/s C. 0.228 T/s D. 0.757 T/s E. 1.52 T/s

3. Induced Forces: Two conducting coils are arranged parallel to each other. The first coil is connected to a power supply so that the current is in at the top and out at the bottom. The voltage on the power supply is being decreased. a. What is the direction (left/right/zero) of the magnetic field (due to the first coil) as it goes through the 2nd coil? b. Is the magnetic flux increasing or decreasing? c. What is the direction of the induced magnetic field through the 2nd coil required to resist the change in magnetic flux? THK ε d. What is the direction (in at top/out at bottom or out at top/in at bottom) of the induced current in the 2nd coil required to produce the induced field needed? e. What is true of the magnetic force between the two coils? • The coils will attract each other. • The coils will repel each other. • There is no magnetic force between the coils. f. What is the direction of the induced current in the 2nd coil if the voltage of the power supply for the first coil…