Answer:
a)[tex]r=1.3933\times 10^{-5}\,m[/tex]
b)[tex]r=3.4675\times 10^{-5}\,m[/tex]
Explanation:
(a)
Given that:
magnetic field,[tex]B=0.9\,T[/tex]
velocity of an electron,[tex]v=2.2\times 10^{6}\,m.s^{-1}[/tex]
we know the charge on an electron,
[tex]q=1.6\times 10^{-19}\,C[/tex]
Since the direction of velocity and magnetic field are not mentioned therefore we assume it to be mutually perpendicular to each other so that it makes a circular trajectory.
For such a case, we have the formula of radius as:
[tex]r=\frac{m.v}{q.B}[/tex]
where m= mass of the charge.
here [tex]m=9.12\times 10^{-31}\,kg[/tex]
[tex]r=\frac{9.12\times 10^{-31}\times 2.2\times 10^{6}}{1.6\times 10^{-19}\times 0.9}[/tex]
[tex]r=1.3933\times 10^{-5}\,m[/tex]
(b)
magnetic field,[tex]B=1.2\,T[/tex]
velocity of an electron,[tex]v=7.3\times 10^{6}\,m.s^{-1}[/tex]
we know the charge on an electron,
[tex]q=1.6\times 10^{-19}\,C[/tex]
Since the direction of velocity and magnetic field are not mentioned therefore we assume it to be mutually perpendicular to each other so that it makes a circular trajectory.
For such a case, we have the formula of radius as:
[tex]r=\frac{m.v}{q.B}[/tex]
where m= mass of the charge.
here [tex]m=9.12\times 10^{-31}\,kg[/tex]
[tex]r=\frac{9.12\times 10^{-31}\times 7.3\times 10^{6}}{1.6\times 10^{-19}\times 1.2}[/tex]
[tex]r=3.4675\times 10^{-5}\,m[/tex]