A loop of wire is lying flat on a tabletop. A uniform magnetic field is directed vertically UPWARDS such that it is perpendicular to the tabletop (and the loop). Beyond the edge of the table, the magnetic field is zero. Imagine that you are looking DOWN on the loop from above. Which of the following statements are true about the induced EMF in the wire loop? You will have to refer to Lenz's Law in order to determine the direction of the induced current.
True/False if the magnetic field suddenly decreases, the induced current will be in a clockwise direction
True/False if you keep the loop on the table, but pull it to the left, the induced current will be in a counter-clockwise direction
True/False if the loop suddenly grows in size, the induced current will be in a clockwise direction
True/False if you pull the loop out of the field (by sliding it off the table), the induced current will be in a clockwise direction
True/False Lenz's Law states that the induced current always leads to a magnetic field that OPPOSES the change in magnetic flux
True/False if the magnetic field suddenly decreases, the induced current will be in a clockwise direction: True. According to Lenz's Law, when the magnetic field through the loop decreases, the induced current will flow in a direction that creates its own magnetic field to oppose the change. In this case, the induced current will flow in a clockwise direction to oppose the decrease in magnetic field.
True/False if you keep the loop on the table, but pull it to the left, the induced current will be in a counter-clockwise direction: False. When you pull the loop to the left, the magnetic field through the loop remains the same. Therefore, there is no change in magnetic flux, and no induced current is generated.
True/False if the loop suddenly grows in size, the induced current will be in a clockwise direction: False. When the loop grows in size, the magnetic field through the loop remains the same. Therefore, there is no change in magnetic flux, and no induced current is generated.
True/False if you pull the loop out of the field (by sliding it off the table), the induced current will be in a clockwise direction: False. When you pull the loop out of the magnetic field, the magnetic field through the loop decreases. According to Lenz's Law, the induced current will flow in a direction that opposes the change, so the induced current will flow in a counter-clockwise direction.
True/False Lenz's Law states that the induced current always leads to a magnetic field that OPPOSES the change in magnetic flux: True. Lenz's Law states that the induced current always flows in a direction that creates a magnetic field that opposes the change in magnetic flux. This is a fundamental principle of electromagnetic induction.
To determine the direction of the induced current, we can use Lenz's Law. Lenz's Law states that the induced current always leads to a magnetic field that opposes the change in magnetic flux.
Now let's analyze each statement:
1. True/False: If the magnetic field suddenly decreases, the induced current will be in a clockwise direction.
False. According to Lenz's Law, if the magnetic field suddenly decreases, the induced current will be in a direction that creates a magnetic field that opposes the change. In this case, the induced current will flow in a counter-clockwise direction to generate a magnetic field that points upwards, opposing the decrease in the magnetic field.
2. True/False: If you keep the loop on the table but pull it to the left, the induced current will be in a counter-clockwise direction.
True. When you pull the loop to the left, the magnetic flux through the loop decreases. According to Lenz's Law, the induced current will flow in a direction that creates a magnetic field opposing the change. In this case, the induced current will flow in a counter-clockwise direction to generate a magnetic field that points downwards, opposing the decrease in magnetic flux.
3. True/False: If the loop suddenly grows in size, the induced current will be in a clockwise direction.
True. If the loop suddenly grows in size, the magnetic flux through the loop increases. According to Lenz's Law, the induced current will flow in a direction that creates a magnetic field opposing the change. In this case, the induced current will flow in a clockwise direction to generate a magnetic field that points upwards, opposing the increase in magnetic flux.
4. True/False: If you pull the loop out of the field (by sliding it off the table), the induced current will be in a clockwise direction.
True. When you pull the loop out of the magnetic field, the magnetic flux through the loop decreases. According to Lenz's Law, the induced current will flow in a direction that creates a magnetic field opposing the change. In this case, the induced current will flow in a clockwise direction to generate a magnetic field that points downwards, opposing the decrease in magnetic flux.
5. True/False: Lenz's Law states that the induced current always leads to a magnetic field that opposes the change in magnetic flux.
True. Lenz's Law explicitly states that the induced current always leads to a magnetic field that opposes the change in magnetic flux. This law helps us determine the direction of the induced current by considering the change in the magnetic field and its effect on the magnetic flux.