Question
Please choose the right answer and explain why it is the right answer.
I got some right, you don't need to explain those, just the ones that have a cross on them.
A cross section of a long solenoid that carries current is shown above. All of the following statements about the magnetic field B inside the solenoid are correct EXCEPT: B is directed to the left. A approximate value for the magnitude of B may be determined by using Ampere's law. The magnitude of B is proportional to the current 1 The magnitude of B proportional to the number of turns of wire per unit length. The magnitude of B is proportional to the distance from the axis of the solenoid. A long straight wire carries a current i; a wire loop lies above the straight wire as shown, or each of the following situations, determine whether the current in the loop is clockwise is counter clockwise is zero (There is no induced current.) changes direction with time. The current i in the long straight wire is to the right and constant. The current i in the long straight wire is to the right and increases with time. The current i in the long straight wire is to the right and decreases with time The current i in the long straight wire starts to the right, decreases to zero at a constant rate, then increases to the left with time. The current i in the long straight wire is constant to the right, and the loop is moved to the right parallel to the wire as shown at right. The current i in the long straight wire is constant to the right, and the loop is moved up away from the wire, as shown at right.
Explanation / Answer
i) zero, because there is no change in the flux linked with the coil
iii) the current is counterclockwise because the outward flux of the coil is decreasing and to balance it, the current is counterclockwise.
iv) the current is counterclockwise, same reason as (iii).