A metre stick is held vertically with one end on the floor and is allowed to fall . What will be the speed of the other end when it hits the floor assuming that the end at the floor does not slip.
ans; 5.4m/s

Here we shall use the law of conservation of energy

for the other end of the meter stick

potential energy = kinetic energy

now, as the scale is rotating as well

mgh = (1/2)mv² + (1/2)Iw²

as v = rw and r = 1m

so,

mgh = (1/2)mv² + (1/2)Iw²

or

mgh = (1/2)v²(m+I)

if we know I then the speed can be calculated using the above relation.