A boy ties a stone of mass $100 \,g$ to the end of a $2$ $m$ long string and whirls it around in a horizontal plane. The string can withstand the maximum tension of $80 \,N$. If the maximum speed with which the stone can revolve is $\frac{ K }{\pi} rev$. / $min$. The value of $K$ is (Assume the string is massless and unstretchable)

Shown here are the velocities and acceleration vectors for a man in several different types of motion. In which case is the man slowing down and turning to the right

A particle moving with uniform speed in a circular path maintains:

Consider a circle of radius $42\  cm$. An insect crawls with uniform speed of $1.3\  cm/s$ along the chord $AB$ then along the circular arc $BCD$ to reach point $D$ and then following cord $DA$ to reach finally $A$. Time spend by the insect to crawl from $A$ to $A$ is closest to    ......... $\sec$

For particle $P$ revolving round the centre $O$ with radius of circular path $r$ and angular velocity $\omega$, as shown in below figure, the projection of $OP$ on the $x$-axis at time $t$ is $.................$.

An object moving in a circular path at constant speed has constant