MHB Mechanics- connected particles

[Shah 72]

Two particles A and B are attached to the ends of a light inextensible string, which passes over a smooth pulley. Particle A has mass 8 kg and particle B has mass 5kg. Both the particles are held 1.2m above the ground. The system is released from rest and the particles move vertically.
a) when particle A hits the ground, it does not bounce. Find the max height reached by particle B
b) when particle A hits the ground, the string is cut. Find the total time from being released from rest until B hits the ground.
I don't understand how to calculate.

 

[Shah 72]

Two particles A and B are attached to the ends of a light inextensible string, which passes over a smooth pulley. Particle A has mass 8 kg and particle B has mass 5kg. Both the particles are held 1.2m above the ground. The system is released from rest and the particles move vertically.
a) when particle A hits the ground, it does not bounce. Find the max height reached by particle B
b) when particle A hits the ground, the string is cut. Find the total time from being released from rest until B hits the ground.
I don't understand how to calculate.

I understood how to calculate. Thanks!

 

[Shah 72]

Two particles A and B are attached to the ends of a light inextensible string, which passes over a smooth pulley. Particle A has mass 8 kg and particle B has mass 5kg. Both the particles are held 1.2m above the ground. The system is released from rest and the particles move vertically.
a) when particle A hits the ground, it does not bounce. Find the max height reached by particle B
b) when particle A hits the ground, the string is cut. Find the total time from being released from rest until B hits the ground.
Iam not getting the ans for (b)
For the time when A hits the ground
V= u+at
t1= 1.02s
Max height traveled by B is 2.68.
When the string is cut, T= 0, a=-g=-10m/s^2
Iam not able to calculate.

 

[maha1]

how

 

[skeeter]

Two particles A and B are attached to the ends of a light inextensible string, which passes over a smooth pulley. Particle A has mass 8 kg and particle B has mass 5kg. Both the particles are held 1.2m above the ground. The system is released from rest and the particles move vertically.
a) when particle A hits the ground, it does not bounce. Find the max height reached by particle B
b) when particle A hits the ground, the string is cut. Find the total time from being released from rest until B hits the ground.

how

$M$ = 8kg, $m$ = 5kg, $T$ is the tension force in the string

$Mg - T = Ma$
$T - mg = ma$

Solve the system of equations for $a$, the magnitude of the acceleration for both masses. Once you find that acceleration, you can find the upward velocity of the smaller mass when the larger one hits the ground …
$v_f^2 = v_0^2 + 2a \Delta y$
At that time, the smaller mass is strictly under the influence of gravity, and one can determine the height the small mass rises above its initial height of 2.4 m, using a variation of the above equation …
$v_f^2 = v_0^2 - 2g \Delta y$

See what you can do from here.