1. The problem statement, all variables and given/known data
If P=0, replace the two remaining couples with a single equivalent couple, specifying its magnitude and the direction of its axis.
3. The attempt at a solution
Position vector of B(rb)=0.3i
Similarly, rd=0.16j+0.17k
∠GCF=atan(16/30)=28.07°
∠DEF=atan(DF/FE)=45°
Then I tried to resolve the forces into its individual components. For 34N force applied at B, in vector form,
[itex]34 \cos 28.07 \hat{i}-34 \sin 28.07 \hat{j}-34 \cos 45 \hat{k} [/itex]
For the other force at B, I can write -18k.
At D, [itex]-34 \cos 28.07 \hat{i}+34 \sin 28.07 \hat{j}+34 \cos 45 \hat{k} [/itex]
Now I take moments of all the above forces about the origin which gives me
1.13i + 7.51j
the magnitude of which is given by [itex]\sqrt{1.13^2+7.51^2} = 7.59[/itex]
which is incorrect according to answer key.
If P=0, replace the two remaining couples with a single equivalent couple, specifying its magnitude and the direction of its axis.
3. The attempt at a solution
Position vector of B(rb)=0.3i
Similarly, rd=0.16j+0.17k
∠GCF=atan(16/30)=28.07°
∠DEF=atan(DF/FE)=45°
Then I tried to resolve the forces into its individual components. For 34N force applied at B, in vector form,
[itex]34 \cos 28.07 \hat{i}-34 \sin 28.07 \hat{j}-34 \cos 45 \hat{k} [/itex]
For the other force at B, I can write -18k.
At D, [itex]-34 \cos 28.07 \hat{i}+34 \sin 28.07 \hat{j}+34 \cos 45 \hat{k} [/itex]
Now I take moments of all the above forces about the origin which gives me
1.13i + 7.51j
the magnitude of which is given by [itex]\sqrt{1.13^2+7.51^2} = 7.59[/itex]
which is incorrect according to answer key.
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