Tag: magnetic field lines due to current

Questions Related to magnetic field lines due to current

The Magnetic effect of current was discovered by:

physics electromagnetism magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop field due to a current carrying coil oersted experiment field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. John Ambrose Fleming

  2. Hans Christian Oersted

  3. Michael Faraday

  4. André-Marie Ampère

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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

physics electromagnetism magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop field due to a current carrying coil oersted experiment field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. Left hand Thumb Rule

  2. Right Hand Thumb Rule

  3. By rotating the conductor

  4. Using sonometer

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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.

physics electromagnetism magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop field due to a current carrying coil oersted experiment field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. downward

  2. Upward

  3. north

  4. south

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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

A loosely wound helix made of stiff wire is mounted vertically with the lower end just touching a dish of mercury when a current from the battery is started in the coil through the mercury

physics magnetic effect of electric current magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop oersted experiment magnetic field lines due to current magnetic field due to current carrying conductor magnetic field on the axis of a toroid

  1. the wire oscillates

  2. the wire continues making contact

  3. the wire breaks contact just when the current is passed

  4. the mercury will expand by heating due to passage of current

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Correct Option: A
Explanation:

According to the Biot Savart's law, a current carrying conductor produces a magnetic field in its surroundings. This will cause the helix to oscillate across a mean position.

A moving charge produces

physics magnetic effects of electric current magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop oersted experiment field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. Neither electric field nor magnetic field

  2. Electro-static field only

  3. Magnetic field only

  4. Both magnetic and electro-static field

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Correct Option: D
Explanation:

A charged particle produces an electric field around it independent of its motion. But when it is at rest, it doesn't produce a magnetic field. 

When it starts moving, it additionally produces a magnetic field too.

The magnetic lines of force due to straight current carrying conductor are:

physics magnetic effects of electric current magnetic field due to a circular current carrying conductor magnetic field produced in a circular loop oersted experiment field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. circular lines

  2. straight lines

  3. concentric lines

  4. elliptical lines

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Correct Option: A

SI unit of permittivity of free space is:

physics moving charges and magnetism field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. Farad

  2. Weber

  3. ${ C }^{ 2 }{ N }^{ -1 }{ m }^{ -2 }$

  4. ${ C }^{ 2 }{ N }^{ -1 }{ m }^{ -1 }$

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Correct Option: C
Explanation:

Coulombic force between two charges is given by

F=1/4π€ (q'.q″/r²)

From here, the SI UNIT of permittivity comes out is

= coulomb²/Newton-meter²

C²/N-m²

If an electron is moving with velocity $\bar{v}$ produces a magnetic field $\bar{B}$, then

physics moving charges and magnetism field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. the direction of field $\bar{B}$ will be same as the direction of velocity $\bar{v}$

  2. the direction of field $\bar{B}$ will be opposite as the direction of velocity $\bar{v}$

  3. the direction of field $\bar{B}$ will be perpendicular as the direction of velocity $\bar{v}$

  4. the direction of field $\bar{B}$ does not depend upon the direction of velocity $\bar{v}$

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Correct Option: C
Explanation:

According to Biot-Savart's law, the magnetic field
$\displaystyle \overset{\rightarrow}{B} = \frac{\mu _o}{4 \pi} . \frac{q (\overset{\rightarrow}{v} \times \overset{\rightarrow}{r} ) }{r^3}$
The direction of $\overset{\rightarrow}{B}$ will be along $\overset{\rightarrow}{v} \times \overset{\rightarrow}{r}$ i.e. perpendicular to the plane containing $\overset{\rightarrow}{v}$ and $\overset{\rightarrow}{r}$.

Biot-Savart law indicates that the moving electrons (velocity $\bar v$ ) produce a magnetic field $\bar B$ such that:

physics moving charges and magnetism field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. $\bar B \perp \bar v$

  2. $\bar B \parallel \bar v$

  3. it obeys inverse cube law.

  4. it is along the line joining the electron and point of observation.

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Correct Option: A
Explanation:

Magnetic field produced by charges moving with velocity $\bar v$, at a distance r is $ \bar B$ = $\left ( \dfrac{\mu _0}{4\pi } \right )$.q$\dfrac{\bar v \times \hat r}{r^2}$
Therefore $\bar B \perp \bar v$

A particle of charge per unit mass $\alpha$  is released from origin with a velocity $\mathop v\limits^ \to   = {v _0}\mathop i\limits^ \wedge  $ in a uniform magnetic field $\mathop B\limits^ \to   =  - {B _0}\mathop k\limits^ \wedge  $ . If the particle passes through (0,y,0) then y is
equal to

physics moving charges and magnetism field due to a current carrying conductor magnetic field due to a straight current carrying conductor magnetic field lines due to current

  1. $ - \frac{{2{v _0}}}{{{B _0}\alpha }}\,\;$

  2. $\frac{{{v _0}}}{{{B _0}\alpha }}\;$

  3. $\;\frac{{2{v _0}}}{{{B _0}\alpha }}$

  4. $ - \frac{{{v _0}}}{{{B _0}\alpha }}$

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Correct Option: C