SAT - Science - Physics - Magnetic Effects of Electric Current

Question - 1

The direction of magnetic field at the centre of a coil carrying in clockwise direction

  • A along the axis of the coil inwards
  • B along the axis of the coil outwards
  • C perpendicular to the axis
  • D none of these

Question - 2

For making a strong electromagnet, the material of the core should be

  • A Soft iron
  • B steel
  • C brass
  • D laminated steel strips

Question - 3

The magnetic lines of force, inside a current carrying solenoid are

  • A perpendicular to the axis and equidistance from each other
  • B circular and they do not intersect each other
  • C along the axis and parallel to each other
  • D circular at the ends but are parallel to the axis

Question - 4

The direction of the induced current is obtained

  • A Fleming's left hand rule
  • B Fleming's right hand rule
  • C Ampere's rule
  • D Maxwell's core screw rule

Question - 5

A soft iron bar is introduced inside a current carrying solenoid. The magnetic field inside the solenoid will

  • A Le zero
  • B remain unaffected
  • C decrease
  • D increase

Question - 6

Magnetic field at the centre of a circular coil of radius r, through which a current I flows is directly proportional to

  • A r
  • B 1/l
  • C l2
  • D l

Question - 7

A moving charge in a magnetic field has

  • A constant velocity
  • B constant K.E
  • C straight line path
  • D none of these

Question - 8

A long current carrying wire which is placed near a current carrying coil, the direction of the force acting on PQ will be

  • A Parallel to PQ towards P
  • B parallel to PQ towards Q
  • C perpendicular to PQ towards right
  • D perpendicular to PQ towards left

Question - 9

A current is flowing in a circular loop of wire in clockwise direction. The magnetic field at the centre of the wire is

  • A directed downward
  • B zero
  • C inversely proportional to the radius of the loop
  • D directed upward

Question - 10

An electron moving in a circular path of radius r makes n rotates per seconds. The magnetic field produced at the centre has the magnitude

  • A zero
  • B \(\frac { { \mu }_{ 0 }ne }{ 2r } \)
  • C \(\frac { { \mu }_{ 0 }ne }{ 2\pi r } \)
  • D \(\frac { { \mu }_{ 0 }n^{ 2 }e }{ 2r } \)