Question

Part D Finally, the switch on the electromagnet is reopened. The magnitude of the external magnetic flux through the wire loop(A. increases, B. decreases, C. remains constant), and there is (A. zero, B. a clockwise, C. a counterclockwise) current induced in the loop (as seen from the left).Part F Now the switch on the electromagnet is reopened. The magnitude of the external magnetic flux through the wire loop (A. increases, B. decreases, C. remains constant), and there is (A. zero, B. a clockwise, C. a counterclockwise) current induced in the loop (as seen from the left.

Part D

Finally, the switch on the electromagnet is reopened. The magnitude of the external magnetic flux through the wire loop ______ (A. increases, B. decreases, C. remains constant), and there is _______ (A. zero, B. a clockwise, C. a counterclockwise) current induced in the loop (as seen from the left).

 

 

Part F

Now the switch on the electromagnet is reopened. The magnitude of the external magnetic flux through the wire loop ______ (A. increases, B. decreases, C. remains constant), and there is _______ (A. zero, B. a clockwise, C. a counterclockwise) current induced in the loop (as seen from the left.

Answer 1

Concepts and reason

The concept required to solve the problem is electormagnet.

When current is flowing through a inductor then an inductor then an induced ${\rm{emf}}$ is induced, electomagnetic law state that a changing magnetic flux through of coil always generate a voltage and the generated voltage is propotential to the rate change of the magnetic flux through the inductor coil.

Initially calculate the magnitude of the external magnetic flux through the wire loop and then find the direction of the current induced in the loop by using right hand rule.

Fundamentals

Write the expression for the induced voltage across inductor.

$e = \frac{{ - d\phi }}{{dt}}$

Here, $e$ is the induced ${\rm{emf}}$ , $\phi$ is the magnetic flux and $t$ is the time.

Write the expression for the induced ${\rm{emf}}$ in terms of the current.

$e = L\frac{{dI}}{{dt}}$

Here, $L$ is the inductor and $I$ is the current.

Right hand rule: When current is flowing through the inductor coil then put thumb in the direction of the current and encircle remaining finger, which provide the direction of the magnetic flux.

(D)

When electromagnet is open then the circuit diagram is as follows:

When circuit is open then the magnitude of the current is decrease and from the expression of the induced ${\rm{emf}}$ it is clear that if the magnitude of the current is decrease then the magnitude of the flux is decreases.

For the determination of the current induced in the loop apply right hand rule which gives the direction of the current is the loop is clock wise.

(F)

When electromagnet is open then the circuit diagram is as follows:

The voltage polarity of the provided electromagnetic is reverse and when switch is open then the direction of current across the inductor is same but the magnitude of the current is decreases in nature therefore, magnitude of the magnetic flux is decreases.

For the determination of the magnetic flux apply right hand thumb rule which provided the direction of the current in the loop in counter clock wise.

Ans: Part D

Decreases, clockwise

Part F

Decreases, counter clock wise.