A particle of mass $m$ describes a circle of radius $r$. The centripetal acceleration of the particle is $4/r^2$. What will be the momentum of the particle?

The driver of a car travelling at velocity $v$ suddenly see a broad wall in front of him at a distance $d$. He should

A body is whirled in a horizontal circle of radius $20 \,cm$. It has angular velocity of $10\, rad/s$. What is its linear velocity at any point on circular path ....... $m/s$

A wheel completes $2000$ revolutions to cover the $9.5\, km$. distance. then the diameter of the wheel is

A car is moving in a circular horizontal track of radius $10\, m$ with a constant speed of $10 \,m/sec$. A plumb bob is suspended from the roof of the car by a light rigid rod of length $1.00\, m$. The angle made by the rod with track is ........ $^o$

A particle describes a horizontal circle of radius $r$ on the smooth surface of an inverted cone as shown. The height of plane of circle above vertex is $h$. The speed of particle should be