A block of mass 2m is hanging at the lower and of a ropeof mass m and length the l, the other end being fixed to the ceililng. A pulse of wavelength `lamda_(0)` is produced at the lower of the rope.

The speed of the pulseat the mid point of rope is:

Options

A. `sqrt((5)/(2))gl`
B. `sqrt((3)/(3)) gl`
C. `sqrt((2)/(5))gl`
D. `sqrt((gl)/(2))`

Answer

A

Explanation

Tension at midpoint `T_(3) = (5)/(2)` mg
`v = sqrt((T_(3))/(mu)) = sqrt((5mg)/(2(m//l)))`
`v = sqrt((5)/(2)) gl.`