Given m=\frac{2m_0}{\sqrt{3}}. Relativistic mass is given by
m=\frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}
Hence,
\frac{m_0}{\sqrt{1-\frac{v^2}{c^2}}}=\frac{2m_0}{\sqrt{3}}
Hence,
\sqrt{1-\frac{v^2}{c^2}}=\frac{\sqrt{3}}{2}
1-\frac{v^2}{c^2}=\frac{3}{4}
\frac{v^2}{c^2}=1-\frac{3}{4}=\frac{1}{4}
v=\frac{c}{2}
Momentum is given by
\begin{align*}
p&=\frac{m_0v}{\sqrt{1-\frac{v^2}{c^2}}}\\
&=\frac{2m_0}{\sqrt{3}}\frac{c}{2}\\
&=\frac{m_0c}{\sqrt{3}}
\end{align*}
Hence, answer is (D)
A transformation is said be canonical if it satisfies Poisson Bracket
\left\{Q,P\right\}_{q,p}=1 i.e.
\frac{\partial Q}{\partial q}\frac{\partial P}{\partial p}-\frac{\partial Q}{\partial p}\frac{\partial P}{\partial q}=1
For (i)
Q = p,
P = -q
\frac{\partial Q}{\partial q}\frac{\partial P}{\partial p}-\frac{\partial Q}{\partial p}\frac{\partial P}{\partial q}=0-1\times-1=1
Hence, transformation is canonical
For (ii) Q = p, P = q
\frac{\partial Q}{\partial q}\frac{\partial P}{\partial p}-\frac{\partial Q}{\partial p}\frac{\partial P}{\partial q}=0-1\times1=-1
Hence, transformation is not canonical
Hence, answer is (B)
Let V be the velocity of frame B with respect to frame A, u_x be the velocity of frame C with respect to frame A, and u_x' be the velocity of frame C with respect to frame B, then we have
{\textstyle u_x'=\frac{u_x-V}{1-u_xV/c^2}\quad\text{and}\quad u_x=\frac{u_x'+V}{1+u_x'V/c^2}}
\begin{align*}
u_x&=\frac{u_x'+V}{1+u_x'V/c^2}\\
&=\frac{\frac{c}{10}+\frac{c}{2}}{1+\frac{c}{10}\frac{c}{2}\frac{1}{c^2}}\\
&=\frac{4}{7}c
\end{align*}
Hence, answer is (B)
Inertia tensor is given by
{\scriptscriptstyle{I}=\begin{pmatrix}
\sum\limits_\alpha\! m_\alpha\left(x_{\alpha,2}^2+x_{\alpha,3}^2\right)&\!-\!\sum\limits_\alpha\! m_\alpha x_{\alpha,1}x_{\alpha,2}&\!-\!\sum\limits_\alpha\! m_\alpha x_{\alpha,1}x_{\alpha,3}\\
-\sum\limits_\alpha\! m_\alpha x_{\alpha,2}x_{\alpha,1}&\!\sum\limits_\alpha\! m_\alpha\left(x_{\alpha,1}^2+x_{\alpha,3}^2\right)&\!-\!\sum\limits_\alpha\! m_\alpha x_{\alpha,2}x_{\alpha,3}\\
-\sum\limits_\alpha\! m_\alpha x_{\alpha,3}x_{\alpha,1}&\!-\!\sum\limits_\alpha\! m_\alpha x_{\alpha,3}x_{\alpha,2}&\!\sum\limits_\alpha\! m_\alpha\left(x_{\alpha,1}^2+x_{\alpha,2}^2\right)
\end{pmatrix}
}
where, \alpha runs over number of particles. Here, x_{\alpha,1} means x-coordinate of particle number \alpha, x_{\alpha,2} means y-coordinate of particle number \alpha and x_{\alpha,3} means z-coordinate of particle number \alpha
For a two-dimensional case, we have
{\scriptstyle{I}=\begin{pmatrix}
\sum\limits_\alpha m_\alpha\left(x_{\alpha,2}^2\right)&-\sum\limits_\alpha m_\alpha x_{\alpha,1}x_{\alpha,2}\\
-\sum\limits_\alpha m_\alpha x_{\alpha,2}x_{\alpha,1}&\sum\limits_\alpha m_\alpha\left(x_{\alpha,1}^2\right)
\end{pmatrix}
}
\begin{align*}
I_{11}&= \sum\limits_\alpha m_\alpha\left(x_{\alpha,2}^2\right)\\
&=m+m+2m+2m\\
&=6m
\end{align*}
\begin{align*}
&I_{12}= -\sum\limits_\alpha m_\alpha x_{\alpha,1}x_{\alpha,2}\\
&={\scriptscriptstyle -(m(-1)(1)+m(1)(-1)+2m(1)(1)+2m(-1)(-1))}\\
&=-(-m-m+2m+2m)\\
&=-2m
\end{align*}
\begin{align*}
&I_{21}= -\sum\limits_\alpha m_\alpha x_{\alpha,2}x_{\alpha,1}\\
&={\scriptscriptstyle -(m(1)(-1)+m(-1)(1)+2m(1)(1)+2m(-1)(-1))}\\
&=-2m
\end{align*}
\begin{align*}
I_{22}&= \sum\limits_\alpha m_\alpha\left(x_{\alpha,1}^2\right)\\
&=m+m+2m+2m\\
&=6m
\end{align*}
{I}=\begin{pmatrix}
6m&-2m\\
-2m&6m
\end{pmatrix}
Hence, xy-component of moment of inertia is -2m
Hence, answer is (D)
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