341If the acceleration of M is a, what is the acceleration of m?
You seem to have taken it as 3a. Its 5a.
In the arrangement shown in the figure,find the acceleration of M.The pulleys and strings are light!
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11 Answers
1i think i got the ans
acc of M = (M-5m)g/(M+15m)...........
1let acceleration M be a & of m be b
see, by equation of constraint u will get
b = 3a
by newtons motion
Mg-2.5T = Ma
2.5T-5mg = mb
where T is tension in rope connecting roof & M
solve & u will get the ans,
one more thing
can u tell me how to use latex in this forum..............
341Are you sure its not g(M-5m)/(M+25m)?
Thats the answer I get.
Logically the minus sign has to be there.
1i m getin same as dimen but prophet frm where dat M+25m come isnt it M+15m
3411********edited
its 5a ......correction
& -ve sign has to be there
3yes the acceleration of m is 5 times that of the acc of M
the eqns are
Mg-(T1+T)=Ma
T-mg=m3a
where T=T1/4
1yes the ans given is correct only..
the constraint eqn is : 5A + a=0 (A= acc of M, a= acc of m)
the force eqns are:
5T-Mg = - MA --- 1
T-mg= -ma ----2
I) now find a and A in terms of T.
II) put in the constarint eq. ... so u will get T.
III) then find a and A from the force equations.. :)
15T-Mg=Ma-----------1
mg-T = 5ma---------2
multiplying eqn 2 wid 5 and thn adding them....we get....5mg- Mg=Ma +25 ma
a=g(5m-M)/M+25m