Home
Class 12
PHYSICS
A bar magnet is held at right angle to a...

A bar magnet is held at right angle to a uniform magneitc field. The couple acting on the acting on the magnet is to be halved by rotating it form this position. The angle of rotation is

A

`60^(@)`

B

`45^(@)`

C

`30^(@)`

D

`75^(@)`

Text Solution

Verified by Experts

As, `tau=MB sintheta`
Where, `theta=90^(@) Rightarrow tau=MB`
`tau_(2)=(1)/(2)tau_(1) Rightarrow MB sintheta=(1)/(2)MB Rightarrow sin theta =(1)/(2) Rightarrow theta=30^(@)`
`therefore "Angle of rotation"=90^(@)-30^(@)=60^(@)`
Promotional Banner

Topper's Solved these Questions

  • MAGNETISM AND MATTER

    DC PANDEY|Exercise 5.2|14 Videos

  • MAGNETISM AND MATTER

    DC PANDEY|Exercise 5.3|15 Videos

  • MAGNETISM AND MATTER

    DC PANDEY|Exercise Medical gallery|1 Videos

  • MAGNETICS

    DC PANDEY|Exercise MCQ_TYPE|1 Videos

  • MODERN PHYSICS

    DC PANDEY|Exercise Integer Type Questions|17 Videos

Similar Questions

Explore conceptually related problems

A "bar" magnet is at right angles to a uniform magnetic field. The couple acting on the magnet is to be one fourth by rotating it from the position. The angle of rotation is

A bar magnet is held perpendicular to a uniform magnetic field. If the couple acting on the magnet is to be halved by rotating it, then the angle by which it is to be rotated is

A bar magnet is held perpendicular to a uniform magnetic field. If the couple acting on the magnet is to be halved by rotating it, then the angle by which it is to be rotated is (A) 30^(@) A bar magnet is held perpendicular to

An emf induced in a coil rotating in a uniform magnetic field is given by

Torque acting on a current loop in a uniform magnetic field is equal to

A bar magnet of magnetic moment M is placed in a magnetic field of inductionB.then maximum Couple acting on it is

A bar magnet is suspended in a uniform magnetic field in a position such that it experiences maxiumum torque. The angle through which it must be rotated from this position such that it experiences half of the maximum torque. The angle through which it must be rotated from this positon such that it experiences half of the maxium troque is

A straight wire of 1.4 m long carries a current of 7 A at right angles to a uniform magnetic field of 0.01 T. Calculate the mechanical force acting on the wire due to the magnetic field.