JEE Main & Advanced Physics Motion in a Straight Line / सरल रेखा में गति JEE PYQ - One Dimensional Motion

The velocity of a particle is\[x\]If its position is\[x\]at\[\frac{{{x}^{2}}}{{{\cos }^{2}}\alpha }-\frac{{{y}^{2}}}{{{\sin }^{2}}\alpha }=1,\]then its displacement after unit time\[\frac{\pi }{4}\]is [AIEEE 2007]

A) \[\pi /6\]

B) \[\pi /3\]

C) \[\pi /4\]

D) \[\pi /2\]

Correct Answer: B

Solution :

[b] The velocity is given as

\[\frac{1}{2}{{\,}^{20}}{{C}_{10}}\]

i.e., \[^{20}{{C}_{10}}\]

\[P(x,\text{ }y)\] \[|~z+4|\le 3,\]

On integrating\[|~z+1|\]

\[D=\left| \begin{matrix} 1 & 1 & 1 \\ 1 & 1+x & 1 \\ 1 & 1 & 1+y \\ \end{matrix} \right|\]

\[x\ne 0\] \[y\ne 0\]