An electric dipole of dipole moment p is lying along uniform electric field E. Calculate the work done in rotating the dipole by 90 degrees.

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Ques: An electric dipole of dipole moment p is lying along uniform electric field E. Calculate the work done in rotating the dipole by 90 degrees.

Ans: The work done in rotating the dipole by 90 degrees when dipole moment is lying along uniform electric field is “pE”.

Explanation: The potential energy of an electric dipole in a uniform electric field is given by an expression: U = -pEcosθ.

where p is the dipole moment,
E is the electric field strength,
θ is the angle between the dipole moment and the electric field.

Initially, the dipole moment is aligned with the electric field, so θ = 0, and the potential energy is:

U1 = -pEcos0 = -pE

When the dipole is rotated by 90 degrees, the angle between the dipole moment and the electric field becomes θ = 90 degrees, and the potential energy becomes:

U2 = -pEcos90 = 0

The change in potential energy is then equal to the work done

Work Done = ΔU = U2 - U1 = 0 - (-pE) = pE

electric dipole of dipole moment p is lying along uniform electric field E

Therefore, the potential energy of the dipole in rotating it by 90 degrees is pE.

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An electric dipole of dipole moment p is lying along uniform electric field E. Calculate the work done in rotating the dipole by 90 degrees.

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2.
Determine the current in the \( 3 \, \Omega \) branch of a Wheatstone Bridge in the circuit shown in the figure.

3.
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4.
When monochromatic light is incident on a surface separating two media, the refracted and reflected light both have the same frequency as the incident frequency but the wavelength of refracted light is different. Explain why.

5.
Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

6.
Assertion : Photoelectric effect is a spontaneous phenomenon. Reason (R): According to the wave picture of radiation, an electron would take hours/days to absorb sufficient energy to overcome the work function and come out from a metal surface.

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dOGVmW

An electric dipole of dipole moment p is lying along uniform electric field E. Calculate the work done in rotating the dipole by 90 degrees.

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2. Determine the current in the \( 3 \, \Omega \) branch of a Wheatstone Bridge in the circuit shown in the figure.

3. Write any two features of nuclear forces.

4.When monochromatic light is incident on a surface separating two media, the refracted and reflected light both have the same frequency as the incident frequency but the wavelength of refracted light is different. Explain why.

5.Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

6.Assertion : Photoelectric effect is a spontaneous phenomenon. Reason (R): According to the wave picture of radiation, an electron would take hours/days to absorb sufficient energy to overcome the work function and come out from a metal surface.

Similar Physics Concepts

Comments

dOGVmW

2.
Determine the current in the \( 3 \, \Omega \) branch of a Wheatstone Bridge in the circuit shown in the figure.

3.
Write any two features of nuclear forces.

4.
When monochromatic light is incident on a surface separating two media, the refracted and reflected light both have the same frequency as the incident frequency but the wavelength of refracted light is different. Explain why.

5.
Suppose a pure Si crystal has \( 5 \times 10^{28} \) atoms per \( \text{m}^3 \). It is doped with \( 5 \times 10^{22} \) atoms per \( \text{m}^3 \) of Arsenic. Calculate majority and minority carrier concentration in the doped silicon. (Given: \( n_i = 1.5 \times 10^{16} \, \text{m}^{-3} \))

6.
Assertion : Photoelectric effect is a spontaneous phenomenon. Reason (R): According to the wave picture of radiation, an electron would take hours/days to absorb sufficient energy to overcome the work function and come out from a metal surface.