IIT JEE-AIEEE 2012, Entrance Notifications, Study Tips, Engineering Preparation, Practice Test Papers, Experts Advice

Ask iit jee aieee pet cbse icse state board community

Discussion Response Post to: Pulley question(Newton's Laws)

Forum Index -> Mechanics -> View Full Question

Author

Message

ramyani chakrabarty (3105)

Blazing goIITian

total posts: 2537
Offline

First, let us consider the system m₁The forces acting on it are :
                      1. wt m₁g vertically downward.
                      2.tension T vertically upward.
acceln is upwards.
eqn: T- m1g=m1a
       T-g=a        ---------------------------(1)
forces acting on the pulley are:

                   1. tension T vertically upwards
                    2.tension 2T1 vertically downward
equn: 2T1-T=0 ----------------------------(2)

system m3
    forces: 1. tension T1 vertically upwards
               2. m3g vertically downward
acceln is (a + a1) downward where a1 is the acceln with wich m3 wud fall in the absence of m1
equn; m3g-T1=m3(a + a1)
            3g-T1=3(a + a1) -------------------------(3)

system m2
        forces:
                 1. tension T1 vertically upwards
               2. m2g vertically downward

acceln is (a -a1) downward where a1 is the acceln with wich m2wud rise in the absence of m1.
           equn: m2g- T1=m2(a -a1)
                   2g-T1=2(a -a1) ---------------------------(4)
these are the equns. solving u get

a=19g/29
a+a1=21g/29
a-a1=17g/29 which r the accelns of m1, m3 and m2

NIT silchar electrical engineering

Like 0 people liked this

Free Sign Up!

Preparing for IIT-JEE ?

Arihant Revision Package for IIT JEE - Books, Practice Tests + Rank Predictor

@ INR 1,995/-

For Quick Info