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Given below are two statements: one is labelled as Assertion A and the other is labelled asReason R. Assertion A:. If oxygen ion (O^-2 ) and Hydrogen ion (H^+ )enter normal to the magnetic field with equal momentum, then the path of O^-2 ion has a smaller curvature than that of H^+. Reason R : A proton with same linear momentum as an electron will form a path of smaller radius of curvature on entering a uniform magnetic field perpendicularly. In the light of the above statements, choose the correct answer from the options given below :

Both A and R are true but R is NOT the correct explanation of A.

Both A and R are true and R is the correct explanation of A.

Magnetic Effects & Magnetism

JEE Main level, single correct, medium

114 of 276

Question 114 of 276

Given below are two statements: one is labelled as Assertion A and the other is labelled asReason R.
Assertion A:. If oxygen ion $\left(\mathrm{O}^{-2}\right)$ and Hydrogen ion $\left(\mathrm{H}^{+}\right)$ enter normal to the magnetic field with equal momentum, then the path of $\mathrm{O}^{-2}$ ion has a smaller curvature than that of $\mathrm{H}^{+}$ .
Reason R : A proton with same linear momentum as an electron will form a path of smaller radius of curvature on entering a uniform magnetic field perpendicularly.
In the light of the above statements, choose the correct answer from the options given below :

Show answer and solution

Answer: (A) $\mathrm{A}$ is true but $\mathrm{R}$ is false.

\begin{aligned} & r=\frac{m v}{q B}=\frac{p}{q B} \\ & r \propto \frac{1}{q}\end{aligned}

Assertion is true reason is false

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