The torque on the rectangular coil due to presence of magnetic field is given,
τ=NIABsinθ
where number of turns N=500,
Current in the coil I=2A,
Area of the coil A=(10×5)10−4m2,
Magnetic field B=2×10−3T,
Angle between area and magnetic field vector is θ
As area vector is always normal to plane and given the plane is parallel to field, so the angle between area and field is 90o.
So, τ=500×2×(10×5)×10−4×(2×10−3)sin90=0.01Nm