SureDen
Torque on a Dipole in a Uniform Field:
consider an electric dipole consisting of charges +q and –q and of length 2a placed in a unifor
Torque or Moment of Force
A force can rotate a nut when applied by a wrench or it can open a door while the door rotates in its hinges (i.e.) in ad
Torque on current loop in a uniform magnetic field:
Torque on a magnetic dipole in a magnetic field:
Moving coil Galvanometer: A galvanometer is a device used to detect current in a circuit.
Principle: If a current carrying coil placed in a magnetic field experiences a torque, the magnitude of which depends on the strength of current.
(i) The metallic parts of machinery are never subjected to a stress beyond elastic limit, otherwise they will get permanently deformed.
(ii) The thickness of the me
Whenever a large conductor i.e. 2 dimension or 3 dimension conductor in placed in varying magnetic field an EMF is induced in it due to the find closed paths within concentric circular currents known as eddy currents.
Eddy currents by nature are con
In a non-uniform electric field, the +q and –q charges of a dipole experiences different forces (not equal and opposite) at slightly different positions in the field and
As shown in fig. consider an electric dipole in a uniform electric field E with its dipole moment 'p' making an angle θ with the field. Two equal and opposite forces -qE
Moment of Inertia
Moment of inertia plays the same role in rotational motion as mass plays
Law of Conservation of Angular Momentum
Newton’s second law for rotational motion
If the upper end of a cylinder is clamped and a torque is applied at the lower end the cylinder gets twisted by angle q. Simultaneously shearing strain is produ
Dimensions of a Physical Quantity.
The powers to which fundamental quantities must be raised in order to express the given physical quantity are called its dimensions.
To make it more clear, consider the physical quantity force
Energy
The energy of a body is defined as its capacity for doing work.
(1) Since energy of a body is the total quantity of work done th
1.The permeability of a magnetic material is 0.9983. Name the type of magnetic materials it represents.
PRE Board E
Limitations of Dimensional Analysis.
(1) Dimensions are not unique. Two Physical Quantities can have same dimensions. For example torque and
Angular Momentum of Satellite.
Angular momentum of satellite L = mvr
⇒
Work, Energy and Power for Rotating Body
Work : If the body is initially at rest and angular disp
For S.H.M. restoring force is proportional to the displacementF∝y o
For S.H.M. (linear) Acceleration µ – (Displacement)
Test Details
A coil of 50 turns is situated in a magnetic field b = 0.25weber/m2 as shown in figure. A current of 2A is flowing in the coil. Torque acting on the coil will be
Test Details
A circular loop of area 1 cm2, carrying a current of 10 A, is placed in a magnetic field of 0.1 T perpendicular to the plane of the loop. The torque on the loop due to the magnetic field is
Test Details
A square coil of N turns (with length of each side equal L) carrying current i is placed in a uniform magnetic field B→=B0j
Test Details
A wire of length L is bent in the form of a circular coil and current i is passed through it. If this coil is placed in a magnetic field then the torque acting on the coil will be maximum when the number of turns is
Test Details
A circular loop of area 1 cm2, carrying a current of 10 A, is placed in a magnetic field of 0.1 T perpendicular to the plane of the loop. The torque on the loop due to the magnetic field is
Test Details
A wire of length L is bent in the form of a circular coil and current i is passed through it. If this coil is placed in a magnetic field then the torque acting on the coil will be maximum when the number of turns is
Test Details
A coil of 50 turns is situated in a magnetic field b = 0.25weber/m2 as shown in figure. A current of 2A is flowing in the coil. Torque acting on the coil will be
Test Details
A square coil of N turns (with length of each side equal L) carrying current i is placed in a uniform magnetic field B→=B0j
Test Details
A magnetic needle lying parallel to a magnetic field requires W units of work to turn it through 60°. The torque required to maintain the needle in this position will be
Test Details
A magnetic needle lying parallel to a magnetic field requires W units of work to turn it through 60°. The torque required to maintain the needle in this position will be
Test Details
A wire of length l is formed into a circular loop of one turn only and is suspended in a magnetic field B. When a current i is passed through the loop, the maximum torque experienced by it is
Test Details
For a system to be in equilibrium, the torques acting on it must balance. This is true only if the torques are taken about
Test Details
A body rotating at 20 rad/sec is acted upon by a constant torque providing it a deceleration of 2 rad/sec2. At what time will the body have kinetic energy same as the initial value if the torque continues to act
Test Details
An engine develops 100 kW, when rotating at 1800 rpm. Torque required to deliver the power is
Test Details
A rigid spherical body is spinning around an axis without any external torque. Due to change in temperature, the volume increases by 1%. Its angular speed
Coming Soon...