A charge particle of charge +q, mass m moving with a velocity uienters a uniform electric field strength E=Ej. Find magnitude of velocity and displacement at time t.

If it has iniitial velocity U i and electric fied is in y direction then it’s x component of velocity does not changes as there no force (if we neglect gravity) . and in y direction it has constant force of E*q and so has an acceleration of Eq/m in y diection So at any time t it has velocity . By using s=ut +1/2a for constant accelaration.

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