Tag: oersted experiment

Questions Related to oersted experiment

In a circular current-carrying conductor, if the current flows in the clockwise direction, the magnetic field direction is __________.

  1. Parallel to the coil towards the observer

  2. Perpendicular to the plane of the coil away from the observer

  3. Perpendicular to the plane of the coil towards the observer

  4. Parallel to the plane of the coil away from the observer


Correct Option: B
Explanation:

The magnetic field are concentric circle at point of a current carrying circular conductor direction of the magnetic field of every section of the circular loop can be found by using the right hand thumb rule .if you curl your right hand fingers in direction of magnetic field your thumb will point in the direction of the current flow.

Consider an experiment where Electric current is flowing in a wire. It is observed that clockwise magnetic field is produced around the wire. A teacher decides to reverse the direction of source battery which results in reversal of electrical current. What will be the effect on magnetic field?

  1. Magnetic field disappears

  2. Direction of field lines reverse

  3. Field lines changes direction to parallel to wire

  4. None of the above


Correct Option: B
Explanation:

Using Right Hand thumb rule, as current direction reverses, you need to reverse the hand and direction of magnetic field reverses.

Axis of a solid cylinder of infinite length and radius $R$ lies along $y$-axis. It carries a uniformly distributed corrent I along +$y$ direction. Magnetic field at a point $(R/2,y,R/2)$ is 

  1. $\cfrac{\mu _{0}I}{4\pi R}\left(\hat{i}-\hat{k}\right)$

  2. $\cfrac{\mu _{0}I}{2\pi R}\left(\hat{j}-\hat{k}\right)$

  3. $\cfrac{\mu _{0}I}{4\pi R}\hat{j}$

  4. $\cfrac{\mu _{0}I}{4\pi R}\left(\hat{j}+\hat{k}\right)$


Correct Option: A

A current carrying circular loop of radius R is placed in the x-y plane with centre at the origin. Half of the loop with x > 0 is now bent so that it now lies in the $y-z$ plane.

  1. The magnitude of magnetic moment now diminishes.

  2. The magnetic moment does not change.

  3. The magnitude of $\bar B$ at $(0,0, z), z$>>R increases.

  4. The magnitude of $\bar B$ at $(0, 0, z), z$>>R is unchanged.


Correct Option: A
Explanation:

For a circular loop of radius R carrying current, I placed in $x-y$ plane, the magnetic moment $M= I\,\,\pi R^2$. It acts perpendicular to the loop i.e., along with the z-direction. When half of the current loop is bent in y-z plane, the magnetic moment due to half current loop in x-y plane,$ M _1 = I \left (\dfrac {\pi R^2}{2} \right )$ acting along z-direction.
Magnetic moment due to half current loop in y-z plane,$ M _2 = I \left (\dfrac {\pi R^2}{2} \right )$ along x-direction.
Effective magnetic moment due to entire bent current loop,
$M'$ =$\sqrt{{M _{1}^{2}}+ {M _{2}^{2}}} $=$\sqrt {{\left (\dfrac{I \pi R^2}{2} \right )^2}+{\left (\dfrac{I \pi R^2}{2} \right )^2}}$
$M'=\dfrac{I\pi R^2}{2}\sqrt2 <M$
i.e., magnetic moment diminishes.

Which of the following entities are closely associated to each other

  1. Gravitation and nuclear fusion

  2. Electricity and magnetism

  3. Chemical Bonding and Planetary motion

  4. None


Correct Option: B
Explanation:

Electric current and magnetism are very closely related phenomenon and both can be generated using the other.

Define Electromagnetism

  1. The study of attraction or repulsion between two magnets is called electromagnetism

  2. The study of electric effects due to magnetic interaction is called electromagnetism

  3. The study of magnetic effects produced due to electric current is called electromagnetism

  4. The study of magnetic effects produced due to electric charge is called electromagnetism


Correct Option: C
Explanation:

Electromagnetism is study of various phenomenon related to electricity and magnetism. 

Which of the following phenomenon can be related to electric current 

  1. Magentism

  2. Gravitation

  3. Nuclear Fission

  4. Chemical Bonding


Correct Option: A
Explanation:

Electric current and magnetism are very closely related phenomenon and both can be generated using the other.

The Magnetic effect of current was discovered by:

  1. John Ambrose Fleming

  2. Hans Christian Oersted

  3. Michael Faraday

  4. André-Marie Ampère


Correct Option: B
Explanation:
The magnetic effect of an electric current was discovered by Hans Christian Oersted in 1820. He demonstrated the effect by plotting compass close to a long straight wire which is carrying current and noting it's deflection. And the by reversing the direction of the current, the compass needle was deflected in the opposite sense.

How can you determine direction of magnetic field lines around a current carrying conductor

  1. Left hand Thumb Rule

  2. Right Hand Thumb Rule

  3. By rotating the conductor

  4. Using sonometer


Correct Option: B
Explanation:

Direction of magnetic field lines around a current carrying conductor can be found by RIght Hand Thumb Rule.

One metal wire is kept in east-west direction.  $I$  is the current flow due west. Then, due to magnetic field  $\vec { { B } }$  of the earth on the wire is in the........ Direction.

  1. downward

  2. Upward

  3. north

  4. south


Correct Option: C
Explanation:
according to left hand rule. if current is in west direction then magnetic field will be north direction, if force is in north west direction