An electric dipole in an electric field that is external is subjected to a torque written as τ = pE sin θ where symbol θ is the angle which is between p and E. The torque tends to align the moment of the dipole p in the direction of E.

What is the formula of dipole?

The formula for electric dipole moment for a pair of equal & opposite charges is p = qd, the magnitude of the charges multiplied by the distance between the two.

What is the torque on a dipole in a field maximum?

Torque is maximum when dipole is held perpendicular to the field.

What is torque on a dipole in a uniform electric field?

Torque (τ) = Force × Distance Separating Forces. τ=dqEsinθ Since dipole moment is given by: p=qd. And the direction of the dipole moment is from the positive to the negative charge, it can see from the above equation that the torque is the cross product of the dipole moment and electric field.

How do you find the force of a dipole?

The formula of the force exerted on an electric dipole by non-uniform electric field. When an electric dipole of moment P is located in a non-uniform electric field E, there is an net force exerted on it. However, the formula of the force in some books is read F=∇(P·E), while in other books, it is F=(P·∇)E.

How is dipole moment calculated?

The dipole moment is calculated by multiplying the distance between the hydrogen and oxygen atoms by the difference in their charge. Then, the angle between the atoms is used to find the net dipole moment. The angle formed by a water molecule is known to be 104.5° and the bond moment of the O-H bond is -1.5D.

What is axis of a dipole?

An electrical dipole consists of two opposite charges attached to a molecule and separated by a certain distance. An attraction of the charges is prevented by the rigidity of the molecular structure. … Figure 2.3 b) shows that the isolated charge is in line with the dipole axis.

What is torque in physics class 12?

Torque is defined as the moment of the externally applied force about a point or axis of rotation.

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.

What is the torque on the dipole when it is perpendicular to the field?

Case(I)→ If the dipole is placed perpendicular to the electric field i.e. θ=90∘, the torque acting on it will be maximum. i.e. Case(II)→ If the dipole is placed parallel to the electric field i.e. θ=0∘ or θ=180∘, the torque acting on it will be minimum.

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At what angle is the torque acting on a dipole half of the maximum torque?

Thus Torque is Maximum only if the angle between the P and E is Maximum i.e, [email protected] has to be Maximum…and [email protected] is maximum only if @ = 90 degree… So Torque is maximum on Dipole if angle between P amd E is 90 degree…. Hope this help…

What is a torque in physics?

torque, also called moment of a force, in physics, the tendency of a force to rotate the body to which it is applied.

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 is the force on a dipole?

The electric dipole consists of two equal charges (q+ and q−) separated by a distance, d. Charges placed nearby experience a force as a result of the electric dipole. The net force is the vector sum of the forces exerted by the two charges, as shown for two different positions.

What is the force between two dipoles?

A dipole is separation of two opposite charges and it is quantified by electric dipole moment and is denoted by p. Angle between the dipole and electric field is 180 degrees. F is positive, so it is a repulsive force.

What is equatorial line of dipole?

Equatorial line is the perpendicular line to the line passing through the positive and negative charges and the point lies on that line is known as the equatorial point.

What is dipole BYJU's?

An electric dipole is defined as a couple of opposite charges q and –q separated by a distance d. By default, the direction of electric dipoles in space is always from negative charge -q to positive charge q. The midpoint q and –q is called the centre of the dipole.

How do you calculate the dipole moment of CO2?

3. In the triatomic CO2 (carbon dioxide) molecule, the dipole moment is zero. Due to the linear structure of the molecule, the dipole moment of C=O. bond (2.3D) on one side of the molecule gets cancelled by that on the other side of the molecule, resulting in net zero dipole moment.

How do you find the dipole moment of h2o?

– There are two hydrogen in water molecules, the two hydrogen creates their individual dipole moments. – We have to calculate the individual dipole moments and later we have to do the sum to get the dipole moment of the water molecule. Therefore the net dipole moment of the water molecule = 0.9187+0.9187=1.837D.

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.

When the dipole is in stable equilibrium the magnitude of torque is?

Note: Stable equilibrium means the lowest potential energy at the equilibrium point. Therefore the stable equilibrium the torque should be zero and the potential energy of the dipole should be minimum.

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.

How do I calculate torque?

To calculate load torque, multiply the force (F) by the distance away from the rotational axis, which is the radius of the pulley (r). If the mass of the load (blue box) is 20 Newtons, and the radius of the pulley is 5 cm away, then the required torque for the application is 20 N x 0.05 m = 1 Nm.

How do you measure torque?

Torque is measured in pounds-feet, meaning a force in pounds acting on the end of a lever measured in feet. For example, if that lug wrench is 2 feet (0.6 m) long, and you put 100 pounds (45.4 kg) of force on it, you are putting 200 pounds-feet (27.65 kg/m) of torque onto the bolt.

How do you write a torque equation?

Mathematically, torque can be written as T = F * r * sin(theta), and it has units of Newton-meters. When the sum of all torques acting on an object equals zero, it is in rotational equilibrium.

How do you find the torque of an axis?

The magnitude of a torque about a fixed axis is calculated by finding the lever arm to the point where the force is applied and using the relation |→τ|=r⊥F | τ → | = r ⊥ F , where r⊥ is the perpendicular distance from the axis to the line upon which the force vector lies.

What is the torque of the force?

Torque is a measure of how much a force acting on an object causes that object to rotate. … In other words, torque is the cross product between the distance vector (the distance from the pivot point to the point where force is applied) and the force vector, ‘a’ being the angle between r and F.

What is torque in physics class 9?

Torque is the measure of the force that can cause an object to rotate about an axis. Force is what causes an object to accelerate in linear kinematics. Similarly, torque is what causes an angular acceleration. Hence, torque can be defined as the rotational equivalent of linear force.

What is the net force and net torque acting on an electric dipole when the dipole free to move is placed along the external uniform electric field ?( 1?

When an electric dipole is placed parallel to a uniform electric field. Net force as well as net torque acting on the dipole is zero.

What is electric dipole Class 12?

The electric dipole is a pair of two equal and opposite charges, +q and −q are separated by a very small distance. … The electric dipole moment of the electric dipole is defined as the product of the magnitude of one of the charges of the dipole and the separation distance between them.

Why torque is unstable at 180 degrees?

At 180°, the potential energy is maximized, so the coil is at the very top of a potential energy maximum. It will rest there with no torque ideally, but even the slightest push will cause it to experience torque and eventually reach 0° due to that torque. For that reason, the 180° configuration is called “unstable.”