Hello guys,,, How is the modulus of E = √(2a^2) for the written E-vector as attached photo ,, Is not it should equal = (a) ?? ((by using this identity (cosx)^2+(sinx)^2 = 1 )) Or there is any mistake by find it ??
What photo? So are you saying that the E = √(200a^2) would alos equal (a)? What does the parens in (a) mean? Is it different than the parens in (2a^2)? If so, how is someone supposed to tell the difference?
You are correct. You might consider throwing this text book away. You basically have the x component is a*cos(θ) and the y component is a*sin(θ). The modulus is the Pythagorean sum of these, so |E| = √[ (a*cos(θ))^2 + (a*sin(θ))^2 ] |E| = √[ (a^2)[cos(θ)^2 + sin(θ)^2] ] |E| = √[ (a^2) ] |E| = |a|