A pair is formed by these equal and opposing parallel forces. This pair applies a torque on the dipole, causing it to spin and align in the field direction. The force, however, is always zero in uniform field.
What is the force in a uniform electric field?
Electric force around a point charge is very similar to gravitational force around a point mass. A uniform electric field consists of two conducting plates. These plates are oppositely charged, and infinitely wide. Obviously, infinitely wide conducting plates do not exist, so uniform electric fields do not exist.
What is the effect of torque on dipole in an electric field?
Answer: Even though the two forces on the ends of the dipole cancel as free vectors, they act at different points. This means that they give rise to a torque on dipole. The turning effect of this torque is to reduce the angle q towards zero, and make the dipole moment vector become parallel to the field.
What is the force on the dipole?
The net force acting on a dipole placed in a uniform electric field is zero. The forces on the two charges constituting the dipole are equal and opposite. Hence, the net force is zero.
What happens to dipole in uniform electric field?
Therefore, the net force on the dipole is zero. Even if we change the orientation, the length and the charge of the dipole, the net force on the dipole will be equal to zero. Hence, the electric force on a dipole when it is placed in a uniform electric field is always zero.
How the torque and net force affected when the same dipole is placed in non uniform electric field?
Magnitude of the two forces are equal but in opposite direction. … Once the dipole is aligned in the direction of field, torque vanishes( r x F will be zero, if r and F are in same direction ). Once the dipole is aligned to electric field, the net force will be zero because they are in opposite direction.
How does torque on the dipole in uniform field depends on its orientation?
Electric dipole will experience a torque when dipole vector is not parallel to electric field direction. The torque τ = p × E = pESinθ. when p and E are parallel then angle θ between the two vectors is zero, hence there will not be any torque.
Does an electric dipole always experience a torque in electric field?
When a dipole is placed in a uniform electric field and dipole vector direction is not parallel to field direction, each chargs of dipole experiences a force. Magnitude of the two forces are equal but in opposite direction. … Hence in uniform field, dipole experiences only torque.
How do you find the torque of a dipole?
τ = (q E sinθ) d = q d E sinθ
Since ‘qd’ is the magnitude of dipole moment (p), and the direction of dipole moment is from positive to negative charge; torque is the cross product of dipole moment and electric field.
What is dipole in a uniform external field?
Electric dipole is a pair of electric charges possessing equal magnitude but opposite charges separated by distance. In simple words, an electric dipole is a separation between positive and negative charges. Dipole in a uniform electric field experiences torque which is a force in rotational motion or an angular force.
What is an electric dipole derive an expression for the torque?
Torque on dipole
The magnitude of the torque is τ = pE sin θ and is maximum when θ = 90o. This torque tends to rotate the dipole and align it with the electric field E . once p is aligned with, the total torque on the dipole becomes zero.
What happens to a dipole in a uniform magnetic field?
When a magnetic rod, (which can be taken as a magnetic dipole), is kept in a uniform magnetic field, the North Pole senses a force equal to the multiplication of the magnetic field intensity and the pole strength in the magnetic field direction.