Several mE 3ts students hole the system of rigid 40 dies in
Solution
solution:
1)M.I. of each body about there C.G> is as follows
i)for rod=Ir=mL^2/12=.8^2/12=.0533 kg m2
ii)for rectangle=Irt=m/12(b^2+h^2)=.3104 kg m2
iii)for disc=Id=mr^2/2=.14 kg m2
iv)for triangle=It=mk^2=.0225 kg m2
2)here weight of rectangle and disc will act through node point and balance at end support but end reaction will not cause torque on system,hence weight at node point are
Mb=2.5/2=1.25 kg
Md=1.75/2=.875 kg
mc=.875+1.25=2.125 kg
hence torque of each element are about C.G. are as follows
i)for rod,Tr=-1.25*9.81*.4=-4.905 kg m2
ii)for rectangle=Trt=1.25*9.81*.5-2.125*.5*9.81=-4.29185 kg m2
iii)for disc=Td=2.125*.4-.875*.4=4.905 kg m2
iv)for triangle=Tt=.875*.375*9.81=3.220 kg m2
for triangle distnace of point D from E=2*h/3=.3752 m
h=.65sin60=.5629 m
3)hence angular accelaration of each memeber are
i)for rod=Tr=Ir*ar
ar=-4.905/.0533=-91.96 rad/s2
ii) for rectangle=Trt=Irt*art
art=-4.29185/.3104=-13.826 rad/s2
iii)for disc=Td=Id*ad
ad=4.905/.14=35.035 rad/s2
iv)for triangle=Tt=It*at
at=3.220/.0225=143.13 rad/s2
