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tropskaerf
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An electric dipole in the x-y plane consists of two opposite charges with magnitudes of 2uC placed 10cm apart. The dipole is placed in an electric field of 10 N/C along the x-axis with a direction of p +45 degrees from the x axis.
1)Determine the magnitude and direction of torque on the dipole
2)How much work will you have to do to move the dipole from 45 degrees to 180 degrees.
So far i know that T= p X E which equals pEsin(theta) and I know that p = QL. Would the charge Q be equal to 2uC as described in the problem? I also don't understand why the dipole would rotate from 45 degrees to 180 degrees rather than down to 0 degrees when both of these directions would follow the electric field is this because of the orientation of the positive and negative charges?
I feel like simply plugging into pEsin(theta) to get QLEsin(theta) = 2uC*10cm*10N/C*sin(45) would be too simple to calculate the torque.
I know that work is the integration of torque between the two angles and that doing so would get me W= pE(cos(theta1)-cos(theta2)) i also feel like plugging in here to get W = -QLE(cos(theta2)-cos(theta1))= -2uC*10cm*10N/C*(cos(180)-cos(45)) would be too simple and not correct.
also, i know that many of these variables are vectors but i don't know how to display the arrows above them on here.
any help would be much appreciated
1)Determine the magnitude and direction of torque on the dipole
2)How much work will you have to do to move the dipole from 45 degrees to 180 degrees.
So far i know that T= p X E which equals pEsin(theta) and I know that p = QL. Would the charge Q be equal to 2uC as described in the problem? I also don't understand why the dipole would rotate from 45 degrees to 180 degrees rather than down to 0 degrees when both of these directions would follow the electric field is this because of the orientation of the positive and negative charges?
I feel like simply plugging into pEsin(theta) to get QLEsin(theta) = 2uC*10cm*10N/C*sin(45) would be too simple to calculate the torque.
I know that work is the integration of torque between the two angles and that doing so would get me W= pE(cos(theta1)-cos(theta2)) i also feel like plugging in here to get W = -QLE(cos(theta2)-cos(theta1))= -2uC*10cm*10N/C*(cos(180)-cos(45)) would be too simple and not correct.
also, i know that many of these variables are vectors but i don't know how to display the arrows above them on here.
any help would be much appreciated