What equation should be written between Node Vc and Vd the Short Circuit

 

Vc and Vd are the same node as far your calculations go.
Note that the voltage across current sources is not zero, as your equation for Va assumes.

 

Vc and Vd are the same node as far your calculations go.
Note that the voltage across current sources is not zero, as your equation for Va assumes.

Thanks

 

Hi,

Do i see this:
Va/30=10
Va=300

That does not look right.

 

Hi,

Do i see this:
Va/30=10
Va=300

That does not look right.

What Should be done

 

What Should be done

Hi,

Well Nodal is based on the sum of ALL the currents into a node, not just the current from one branch.
For example if we have three resistors all having one terminal connected to a single node Vx and each having voltage v1,v2,v3 on their other terminals then the equation is:
(v1-Vx)/R1+(v2-Vx)/R2+(v3-Vx)/R3=0

so you see the sum of all three currents into the node is zero. We can not just do (v1-Vx)/R1=0 for example because that is only one of the currents into the node.

 

Hi,

Well Nodal is based on the sum of ALL the currents into a node, not just the current from one branch.
For example if we have three resistors all having one terminal connected to a single node Vx and each having voltage v1,v2,v3 on their other terminals then the equation is:
(v1-Vx)/R1+(v2-Vx)/R2+(v3-Vx)/R3=0

so you see the sum of all three currents into the node is zero. We can not just do (v1-Vx)/R1=0 for example because that is only one of the currents into the node.

Thanks
That helped