Question 73: Magnetism and Matter

Question

A rigid wire consists of a semicircular portion of radius $$R$$ and two straight sections. The wire is partially immerged in a perpendicular magnetic field $$B=B_0 \hat{k}$$ as shown in figure. The magnetic force on the wire if it has a current $$i$$ is:

Accepted Answer

Note : Direction of magnetic field is in $$+\hat{k}$$
$$\begin{aligned}
& \overrightarrow{\mathrm{F}}=\mathrm{i} \vec{\ell} 	imes \overrightarrow{\mathrm{B}} \
& \ell=2 \mathrm{R} \
& \overrightarrow{\mathrm{F}}=-2 \mathrm{iRB} \hat{\mathrm{j}}
\end{aligned}$$

Answer

$$i B R \hat{j}$$

Answer

$$-2 i B R \hat{j}$$

Answer

$$2 i B R \hat{j}$$

Answer

$$-i B R \hat{j}$$

Magnetism and Matter

A rigid wire consists of a semicircular portion of radius $R and two straight sections. The wire is partially immerged in a perpendicular magnetic field B=B_0 \hat{k} as shown in figure. The magnetic force on the wire if it has a current i$ is:

Choose the correct answer: