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The mass of an electron of charge 'e' is...

The mass of an electron of charge 'e' is 'm'. The electron is moving in a straight line accelarated by a potential difference V. If enters a crossed field where E and B are the 'intensities' of electric and magnetic fields respectively acting matually perpendicular top the direction of motion of elctron . Prove that for no deflection of the electron, `frac(e)(m)=frac(E^2)(2VB^2)`.

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UNITED BOOK HOUSE-MODEL PAPER SET-01-EXERCISE
  1. Why do we prefer a potentiometer with longer wire?

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  2. An electric bulb is connected to battery of e.m.f. 10V and 0.01 A curr...

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  3. The mass of an electron of charge 'e' is 'm'. The electron is moving i...

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  4. Which of the following relation represent Biot-Savart's law?

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  5. Which of the following, if any, can act as a source of electromagneti...

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  6. Which of the following, if any, can act as a source of electromagneti...

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  7. Which of the following, if any, can act as a source of electromagneti...

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  8. Hydrogen atom has one elctron. How then many lines are originated in h...

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  9. Explain how radioactive nuclei can emit beta-particle even though atom...

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  11. State Gauss's law in electrostatics. Proof of gauss law.

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  13. State Ampere's circuital law. Using this law obtain an expression fo...

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  15. Describe Davission and Germer experiment to establish the wave nature...

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  20. What is the time taken by A.C. of 50 Hz to invert its direction?

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