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A particle of mass m and charge q has an...

A particle of mass m and charge q has and initial velocity `vecv = upsilon_(0)hatj`. If an electric field `vec E=vec_(0) hat i` and magnetic field `vec B=B_(0)hat i` act on the particle, its speed will double after a time :

A

`t = (2m v_(0))/(qE_(0))`

B

`t = (2 B_(0)q)/(mv_(0))`

C

`t = (sqrt(3) B_(0)q)/(mv_(0))`

D

`t = (sqrt(3) m v_(0))/(qE_(0))`

Text Solution

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The correct Answer is:
D
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