Table of Contents
- 1 What happens when a switch is closed in a transformer?
- 2 What happens to the deflection of the galvanometer needle when the switch is closed?
- 3 What happens to solenoid when switch is closed?
- 4 What happens when current flows in the secondary of a transformer?
- 5 Why did the galvanometer needle deflects in the experiment?
- 6 What happens if you keep the bar magnet stationary in the coil?
- 7 How to measure the deflection of current in galvanometer?
- 8 Why does the needle of a galvanometer move in a direction?
What happens when a switch is closed in a transformer?
If the switch is closed, an emf will be induced on the second solenoid, which amplifies the car battery’s voltage. The question is what happens when the switch is open and suggest a useful practical modification to the primary circuit.
What happens to the deflection of the galvanometer needle when the switch is closed?
Closed suddenly: when the switch is closed suddenly, the Galvanometer needle shows a small momentary deflection and then returns to zero. Finally opened: at the last case, when the switch is finally opened, the Galvanometer shows a small momentary deflection in the opposite direction and then comes back to zero.
When switch S is first closed the needle of the galvanometer deflects briefly then returns to zero?
When the switch is closed, a current is established in the primary coil, and a magnetic field is created around the coil. The galvanometer needle deflects for an instant and quickly returns to a zero current reading, indicating that a current was established in the secondary coil for a brief moment.
Why does brief deflection occur?
This is due to the change in magnetic flux in the coil. Due to change in magnetic flux, an induced emf is produced in the coil.
What happens to solenoid when switch is closed?
“When a circuit is closed (by a switch), there will be a quick increase in current, which will induce a magnetic field in the solenoid. The same magnetic field causes a change in the magnetic flux linkage of the coils, which then produces a back emf. “
What happens when current flows in the secondary of a transformer?
When an electrical load is connected across the secondary winding of a transformer, current flows through the secondary and the load. The magnetic field produced by the current in the secondary interacts with the magnetic field produced by the current in the Page 16 primary.
What will happen to the galvanometer in coil B if the key is suddenly closed in coil A and why?
When key is closed galvanometer will show a momentary deflection due to produce of induced current due to change in magnetic field lines. And when key is opened again a momentary deflection will be seen but at opposite direction due to again a change in magnetic fields..
Why is there a deflection of the needle on the galvanometer when a magnet approaches or retreats from the coil?
There is no battery or power supply, so no current should flow. If the magnet is held stationary near, or even inside, the coil, no current will flow through the coil. If the magnet is moved, the galvanometer needle will deflect, showing that current is flowing through the coil.
Why did the galvanometer needle deflects in the experiment?
Answer: When the magnet is moved away from the coil, the galvanometer shows deflection in the opposite direction indicating the direction of induced current in the reversed direction. This indicates that when there is a relative motion between the coil and the magnet a current is induced in the coil.
What happens if you keep the bar magnet stationary in the coil?
If the magnet is held stationary near, or even inside, the coil, no current will flow through the coil. If the magnet is moved, the galvanometer needle will deflect, showing that current is flowing through the coil.
What happens to the deflection of the galvanometer?
The direction of deflection in a galvanometer is reversed if the direction of motion (or polarity of the magnet) is reversed. This indicates that whenever there is a change in the magnetic flux linked with a coil, an emf is induced.
What is the deflection in galvanometer?
galvanometer, instrument for measuring a small electrical current or a function of the current by deflection of a moving coil. The deflection is a mechanical rotation derived from forces resulting from the current.
How to measure the deflection of current in galvanometer?
This is only possible in the case of DC current. Try switching the wires, you give to galvanometer while measuring DC current, the galvanometer at first shows deflection in one way but when switch the polarity, the galvanometer’s needle deflect in a different direction.
Why does the needle of a galvanometer move in a direction?
This is because the galvanometer’s needle moves in a direction according to the direction of current. This is only possible in the case of DC current.
What is the difference between galvanometer and AC current?
Galvanometer deflects in the direction of current. But ac current, as the name suggests (Alternating current) alters in positive and negative direction. So, Galvanometer cannot show deflection again and again in the positive direction of current. Why do we use a headphone instead of a galvanometer in an AC bridge?