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jfoster
October 15, 2019, 07:59 PM
I had a question very similar to this.

If a phasor B = 6 – j2 is subtracted from phasor A = -4 + j3, what is the resulting phasor C?

Any idea how to solve for it?

Thanks,
John

dash1911
October 16, 2019, 01:27 PM
I had a question very similar to this.

If a phasor B = 6 – j2 is subtracted from phasor A = -4 + j3, what is the resulting phasor C?

Any idea how to solve for it?

Thanks,
John

John,

This is one of those questions that seems more complicated than it really is. This form of phasor is Z=R+jX where R is the real part of the phasor, and X is the imaginary part of the phasor. When adding/subtracting in this form, it is as easy as adding/subtracting each part of the phasor individually. Given phasor Z1 and phasor Z2, Z1-Z2=(R1-R2) + j(X1-X2) So, C = A - B = [(-4)-6] +j[3-(-2)] = -10 + j5. This only works for addition and subtraction. I hope this helps!

Dana

jfoster
October 16, 2019, 07:09 PM
John,

This is one of those questions that seems more complicated than it really is. This form of phasor is Z=R+jX where R is the real part of the phasor, and X is the imaginary part of the phasor. When adding/subtracting in this form, it is as easy as adding/subtracting each part of the phasor individually. Given phasor Z1 and phasor Z2, Z1-Z2=(R1-R2) + j(X1-X2) So, C = A - B = [(-4)-6] +j[3-(-2)] = -10 + j5. This only works for addition and subtraction. I hope this helps!

Dana

Thank you