Question 58: Magnetism and Matter

Question

A uniform magnetic field of $$2 	imes 10^{-3} \mathrm{~T}$$ acts along positive $$Y$$-direction. A rectangular loop of sides $$20 \mathrm{~cm}$$ and $$10 \mathrm{~cm}$$ with current of $$5 \mathrm{~A}$$ is in $$Y-Z$$ plane. The current is in anticlockwise sense with reference to negative $$X$$ axis. Magnitude and direction of the torque is:

Accepted Answer

$$\begin{aligned}
& \overrightarrow{\mathrm{M}}=\mathrm{i} \overrightarrow{\mathrm{A}} \
& =5 	imes(0.2) 	imes(0.1)(-\hat{\mathrm{i}}) \
& =0.1(-\hat{\mathrm{i}}) \
& \vec{	au}=\overrightarrow{\mathrm{M}} 	imes \overrightarrow{\mathrm{B}}=0.1(-\hat{\mathrm{i}}) 	imes\left(2 	imes 10^{-3}ight)(\hat{\mathrm{j}}) \
& =2 	imes 10^{-4}(-\hat{\mathrm{k}}) \mathrm{N}-\mathrm{m}
\end{aligned}$$

Answer

$$2 	imes 10^{-4} \mathrm{~N}$$- $$\mathrm{m}$$ along negative $$Z$$-direction

Answer

$$2 	imes 10^{-4} \mathrm{~N}$$ - $$\mathrm{m}$$ along positive $$X$$-direction

Answer

$$2 	imes 10^{-4} \mathrm{~N}$$ - $$\mathrm{m}$$ along positive $$Y$$-direction

Answer

$$2 	imes 10^{-4} \mathrm{~N}$$ - $$\mathrm{m}$$ along positive $$Z$$-direction

Magnetism and Matter

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