Physics
In the figure given below, when the key is pressed, a current passes in the wire in the direction from A to B (i.e., from south to north). The north pole of the compass needle will deflect towards:
- East
- North
- South
- West
Answer
West
Reason — When a current passes through a wire from south to north (A to B), it generates a magnetic field around the wire. According to the right-hand rule for electromagnetism, if you wrap your right-hand fingers around the wire in the direction of the current, your thumb will point in the direction of the magnetic field.
So, with the current flowing from A to B, if you curl your fingers around the wire, your thumb would point towards the west. This indicates that the magnetic field is directed towards the west.
Related Questions
In the figure given below, current is passed in a downward direction through a cardboard. The magnetic field lines would be :
- straight lines
- concentric circles
- elliptical lines
- squares
According to the right hand thumb rule, the thumb points in the direction of …………… and fingers encircle the wire in direction of ……………
- magnetic field lines, current
- electric field lines, current
- current, magnetic field lines
- none of the above
In the figure given below, the direction of current in the loop is …………… . So, it behaves as a …………… .
- anticlockwise, south pole
- anticlockwise, north pole
- clockwise, north pole
- clockwise, south pole
Which of the following statements is not true ?
- The strength of magnetic field due to a bar magnet can be changed.
- A solenoid behaves like a bar magnet i.e. it attracts iron filings.
- The magnetic field increases if a soft iron core is placed along the axis of solenoid.
- The magnetic field lines inside the solenoid are nearly straight and parallel to the axis of solenoid.