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COMEDK2015PhysicsElectrostatics

An electric dipole consists of two opposite charges, each of magnitude 1.0 C separated by a distance of 2.0 ~cm . The dipole is placed in an external field of 10⁵ NC ⁻¹ . The maximum torque on the dipole is

Options

  1. A0.2 10⁻³ ~N - m
  2. B1 10⁻³ ~N - m
  3. C2 10⁻³ ~N - m
  4. D4 10⁻³ ~N - m

Correct answer

C. 2 10⁻³ ~N - m

Step-by-step solution

aligned |q₁ | &= |q₂ |=1 C =10⁻⁶ C 2 l=2 ~cm =2 10⁻² ~m E=10⁵ NC ⁻¹ Maximum torque, _ &=p E 90^ &=p E=q(2 l ) E &=10⁻⁶ 2 10⁻² 10⁵ &=2 10⁻³ ~N - m aligned

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