JEE Main202522 Jan 2025Evening ShiftPhysicsMagnetic Effects of CurrentActual
A proton is moving undeflected in a region of crossed electric and magnetic fields at a constant speed of 2 10^5 ~ms ⁻¹ . When the electric field is switched off, the proton moves along a circular path of radius 2 cm . The magnitude of electric field is x 10^4 ~N / C . The value of x is _______ Take the mass of the proton =1.6 10⁻²⁷ ~kg .
Correct answer
0
Step-by-step solution
aligned & B v q=E q & E=B v & r= v m B q & B= m v r q & E= ( m v r q ) v= m v^2 r q & = 1.6 10⁻²⁷ 4 10¹⁰ 2 10⁻² 1.6 10⁻¹⁹ & =2 10^4 ~N / C & x=2 aligned