A proton and an alpha particle both enter a region of uniform magnetic field B, moving at right angles to the field B. If the radius of circular orbits for both the particles is equal and the kinetic energy acquired by proton is 1 MeV, the energy acquired by the alpha particle will be

Moving Charges and Magnetism question

2015 · Q116

Moving Charges and Magnetism question

2015 · Q116

View written solutionFree

Correct answer: B

As we know, F = qvB = ${{m{v^2}} \over R}$

$\therefore$ $R = {{mv} \over {qB}} = {{\sqrt {2m\left( {kE} \right)} } \over {qB}}$

Since R is same so, $KE \propto {{{q^2}} \over m}$

Therefore KE of $\alpha$ particle

$= {{{q^2}} \over m} = {{{{\left( 2 \right)}^2}} \over 4} = 1\,MeV$

More from Moving Charges and Magnetism

An electron moving in a circular orbit of radius r makes n rotations per second. The magnetic field produced at the centre has magnitude2015 · MCQ
A conducting square frame of side 'a' and a long straight wire carrying current $I$ are located in the same plane as shown in the figure. The frame moves to the right with a constant velocity 'V'. The emf induced in the frame will be… Includes diagram2015 · MCQ
A wire carrying current $I$ has the shape shown in adjoining figure. Linear parts of the wire are very long and parallel to X-axis while semicircular protion of radius R is lying in Y-Z plane. Magtnetic field at pont $O$ is Includes diagram2015 · MCQ
Two identical long conducting wires $A O B$ and $C O D$ are placed at right angle to each other, with one above other such that $O$ is their common point for the two. The wires carry $I$ 1 and $I$ 2 currents, respectively. Point $P$ is lying at…2014 · MCQ
In an ammeter 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, the resistance of ammeter will be2014 · MCQ
A long straight wire carries a certain current and produces a magnetic field 2 $\times$ 10 $-$ 4 Wb m $-$ 2 at a perpendicular distance of 5 cm from the wire. An electron situated at 5 cm from the wire moves with a velocity 107 m/s towards…2013 · MCQ
A circular coil ABCD carrying a current 'i' is placed in a uniform magnetic field. If the magnetic force on the segment AB is $F$ , the force on the remaining segment BCDA is Includes diagram2013 · MCQ
When a proton is released from rest in a room, it starts with an initial acceleration $a$ 0 towards west. When it is projected towards north with a speed $v$ 0 it moves with an initial acceleration 3 $a$ 0 towards west. The an initial…2013 · MCQ

Sign in

Moving Charges and Magnetism question

2015 · Q116

Moving Charges and Magnetism question

2015 · Q116

View written solutionFree

Correct answer: B

As we know, F = qvB = ${{m{v^2}} \over R}$

$\therefore$ $R = {{mv} \over {qB}} = {{\sqrt {2m\left( {kE} \right)} } \over {qB}}$

Since R is same so, $KE \propto {{{q^2}} \over m}$

Therefore KE of $\alpha$ particle

$= {{{q^2}} \over m} = {{{{\left( 2 \right)}^2}} \over 4} = 1\,MeV$