When a magnetic field is applied in a direction perpendicular to the direction of cathode rays, then their

  • A

    Energy decreases

  • B

    Energy increases

  • C

    Momentum increases

  • D

    Momentum and energy remain unchanged

Similar Questions

A charge of $1\,C$ is moving in a magnetic field of $0.5\,Tesla$ with a velocity of $10\,m/sec$ Perpendicular to the field. Force experienced is.....$N$

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A particle having a mass of $10^{- 2} \,kg$ carries a charge of $5 \times 10^{-8}\, C.$ The particle is given an initial horizontal velocity of $10^5\, m/s $ in the presence of electric field $E$ and magnetic field  $B.$ To keep the particle moving in a horizontal direction, it is necessary that

$(1)$ $\vec B$ should be perpendicular to the direction of velocity and $\vec E$ should be along the direction of velocity
$(2)$  Both $\vec B$ and $\vec E$ should be along the direction of velocity
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Which one of the following pairs of statements is possible?

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