Ansari Sir was demonstrating an experiment in his class with the setup as shown in the figure below.
A magnet is attached to a spring. The magnet can go in and out of the stationary coil.
He lifted the Magnet and released it to make it oscillate through the coil. Based on your understanding of the phenomenon, answer the following questions.
a. What is the principle which Ansari Sir is trying to demonstrate?
Answer
- The teacher is trying to demonstrate the principle of Electromagnetic Induction .
- It states that a current is produced when the magnetic field through a loop changes .
b. What will be observed when the Magnet starts oscillating through the coil. Explain the reason behind this observation.
Answer
- Current is induced in the coil due to relative motion between the magnet and the coil .
- Changing the magnetic field around the coil generates induced current .
c. Consider the situation where the Magnet goes in and out of the coil. State two changes which could be made to increase the deflection in the galvanometer.
Answer
Using a stronger magnet or using a coil with more number of turns .
OR
Is there any difference in the observations in the galvanometer when the Magnet swings in and then out of the stationary coil? Justify your answer.
Answer
a. Sir is trying to demonstrate the principle of Electromagnetic induction.
b. There will be induced current in the coil due to relative motion between the magnet and the coil. Changing the magnetic field around the coil generates induced current.
c. Using a stronger magnet, using a coil with more number of turns.
When the magnet moves into the coil, the ammeter shows a momentary deflection towards one side say left.
When the magnet moves out of the coil, the ammeter shows a momentary deflection now towards right.
This is due to changing magnetic field /flux associated with the coil as the magnet moves in and out.
Alternatively, the flux increases when the magnet goes in and it decreases when the magnet goes out.
