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cathelyn13

Member

Registered: 2009-07-18

Posts: 10

Mechanics - Newton's law of motion

Particles of masses 0.7kg and 0.3kg are attached to the ends of a light inextensible string which passes over a smooth pulley. The system is released from rest and the particles move vertically.
i) Find the tension in the string
ii) State the magnitude of the resultant force exerted on the pulley by the string.

Thanks in advance!!!

jk22

Member

Registered: 2010-06-14

Posts: 33

Re: Mechanics - Newton's law of motion

Hallo, nice to meet you. I'm new in here.

let g be the acceleration of gravity, (i.e ~9.81m/s^2)

i) the tension is the sum of forces acting on a point of the string, hence : (0.7-0.3)g kg*m/s^2

ii) on the pulley act a  force of (0.3+0.7)g=1g kg*m/s^2 (vertical)

Hope this is in some way right.

c ya.