Torque on Charges in an Electric Field

AI Thread Summary
The problem involves calculating the maximum torque on a dipole formed by two charged spheres in a uniform electric field. The formula used is t = qEL, where q is the charge, E is the electric field strength, and L is the distance between the charges. The calculated torque is 3.15 x 10^-4 Nm, which is the correct unit for torque, not Joules. The discussion clarifies that torque is indeed measured in Newton-meters (Nm), confirming the solution's correctness. Understanding the distinction between torque and energy units is crucial for solving similar problems.
Mitchtwitchita
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Homework Statement



Two small plastic spheres, one charged to 17 nC and the other to -17 nC, are connected by a 25-mm long insulating rod. Suppose this dipole is placed in a uniform electric field with strength 7.4 x 10^5 N/C. What is the maximum possible torque on the dipole?

Homework Equations



t = qEL


The Attempt at a Solution



t = qEL
=(17 x 10^-9 C)(7.4 x 10^5 N/C)(2.5 x 10^-2 m)
=3.15 x 10 ^-4 J
This can't be right. Is torque measured in Joules? Can somebody please help me out with this problem?
 
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Your unit is Nm, which is right for torque, not the equivalent J for energy.
 
How about the solution?
 
Looks correct to me.
 

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