A block of mass $M$ has a circular cut with a frictionless surface as shown. The block rests on the horizontal frictionless surface of a fixed table. Initially the right edge of the block is at $x=0$, in a co-ordinate system fixed to the table. A point mass $m$ is released from rest at the topmost point of the path as shown and it slides down. When the mass loses contact with the block, its position is $\mathrm{x}$ and the velocity is $\mathrm{v}$. At that instant, which of the following options is/are correct?
(image)
$[A]$ The $x$ component of displacement of the center of mass of the block $M$ is : $-\frac{m R}{M+m}$.
[$B$] The position of the point mass is : $x=-\sqrt{2} \frac{\mathrm{mR}}{\mathrm{M}+\mathrm{m}}$.
[$C$] The velocity of the point mass $m$ is : $v=\sqrt{\frac{2 g R}{1+\frac{m}{M}}}$.
[$D$] The velocity of the block $M$ is: $V=-\frac{m}{M} \sqrt{2 g R}$.
$A,C$
$A,B$
$A,D$
$A,C,D$
A uniform chain of length $3\, meter$ and mass $3\, {kg}$ overhangs a smooth table with $2\, meter$ laying on the table. If $k$ is the kinetic energy of the chain in joule as it completely slips off the table, then the value of ${k}$ is (Take $\left.g=10\, {m} / {s}^{2}\right)$
A rain drop of radius $2\; mm$ falls from a helght of $500 \;m$ above the ground. It falls with decreasing acceleration (due to viscous resistance of the air) until at half its original hetght, it attains its maximum (terminal) speed, and moves with uniform speed thereafter. What is the work done by the gravitational force on the drop in the first and second half of its journey ? What is the work done by the resistive force in the entire journey if its speed on reaching the ground is $10\; m s ^{-1} ?$
A small ball falling vertically downward with constant velocity $4m/s$ strikes elastically $a$ massive inclined cart moving with velocity $4m/s$ horizontally as shown. The velocity of the rebound of the ball is
A demonstration apparatus on a table in the lab is shown in diagram. It consists of a metal track (shown as a thick solid line in the figure below) along which a perfectly spherical marble which can roll without slipping. In one run, the marble is released from rest at a height h above the table on the left section, rolls down one side and then up the other side without slipping, briefly stopping when it has reached $h_1$. Assuming the table to be horizontal and neglecting air drag as well as any energy loss due to rolling,
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