A charge particle of mass `m=5gm` and charge `q=12 muC`enters along `AB` at point `A` in a uniform magnetic field of magnitude `B=100` Tesla existing in a rectangular region of size `(8m xx 6m)` and into the plane of paper as shown in figure. The particle leaves the region at `'C'`. The speed of the charge particle (in m/s) as it leaves the region is

Answer

2

Explanation

`r=(mv)/(qB)`
`sintheta=a/r, costheta=(r-b)/r`
`(a/r)^(2)+((r-b)/r)^(2)=1`
`impliesr=((a^(2)+b^(2)))/(2b)=(mv)/(qB)`
`v=(qB(a^(2)+b^(2)))/(2mb)=2m//s`