pulley question

[kasheee]

Particles of mass 3kg and 5kg are attached by a light inextensible string, which passes over a smooth fixed pulley.

The 5kg particle is 3m above the ground. The system is released from rest. Find its acceleration.

***********************

Could some check my working out please:

T=tension

for 3kg

T=3a

for 5kg

5g-T=5a

equating the two equations and I get 5g/8=a

Thanks.

 

[Deleted member 4993]

Particles of mass 3kg and 5kg are attached by a light inextensible string, which passes over a smooth fixed pulley.

The 5kg particle is 3m above the ground. The system is released from rest. Find its acceleration.

***********************

Could some check my working out please:

T=tension

for 3kg

T=3a

for 5kg

5g-T=5a

equating the two equations and I get 5g/8=a

Thanks.

If the 3 kg particle is resting on a smooth table and the 5 kg particle is pulled by gravity.

Then

T = 3a

5g - T = 5a

a = 5/8 * g

If both the particles are hanging from the pulley (to the ground)

5*g - T = 5*a

T - 3*g = 3*a

a = 2*g/8 = g/4

T = 3*g/4 + 3*g = 15/4 * g

 

[kasheee]

Thanks for your help.