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KVPY2013PhysicsElectrostatics

An electron with an initial speed of 4.0 10⁶ ~ms ⁻¹ is brought to rest by an electric field. The mass and charge of an electron are 9 10⁻³¹ ~kg and 1.6 10⁻¹⁹ C , respectively. Identify the correct statement

Options

  1. AThe electron moves from a region of lower potential to higher potential through a potential difference of 11.4
  2. BThe electron moves from a region of higher potential to lower potential through a potential difference of 11.4
  3. CThe electron moves from a region of lower potential to higher potential through a potential difference of 45 ~
  4. DThe electron moves from a region of higher potential to lower potential through a potential difference of 45 ~

Correct answer

D. The electron moves from a region of higher potential to lower potential through a potential difference of 45 ~

Step-by-step solution

array l q V= 1 2 m v² V= 1 2 m v² q V= 1 2 9 10⁻³¹ (4 10⁶ )² 1.6 10⁻¹⁹ =45 V array 45 ~V from higher to lower potential.

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