153706 Two electrons with initial speed $8 \times 10^{6} \mathrm{~m} / \mathrm{s}$ are released into a space with magnetic field $B$. The first electron is released along the $\mathrm{X}$-axis and it moves in a straight line. The second electron is shot from the origin along the $\mathbf{Y}$-axis and it moves in a circle that intersects the $\mathrm{Z}$-axis at: $=$ $+18 \mathrm{~cm}$. The magnitude and direction of $\vec{B}$ is $\left(\mathrm{m}_{\mathrm{e}}=\mathbf{9} \times 10^{-31} \mathrm{~kg}\right)$

153707 A beam of protons enters a uniform magnetic field of $0.314 \mathrm{~T}$ with a velocity $4 \times 10^{5} \mathrm{~ms}^{-1}$ in a direction making an angle $60^{\circ}$ with the direction of the magnetic field. The path of the beam is (mass of proton $=1.6 \times 10^{-27} \mathrm{~kg}$ )

153708 A proton is moving with a uniform velocity of $10^{6} \mathrm{~ms}^{-1}$ along the $\mathrm{Y}$-axis, under the joint action of a magnetic field along $Z$-axis and an electric field of magnitude $2 \times 10^{4} \mathrm{Vm}^{-1}$ along the negative $\mathrm{X}$-axis. If the electric field is switched off, the proton starts moving in a circle. The radius of the circle is nearly
$\text { (given : } \left.\frac{\mathrm{e}}{\mathrm{m}} \text { ratio for proton } \approx 10^{8} \mathrm{Ckg}^{-1}\right)$

153709 A particle of charge $-16 \times 10^{-18} \mathrm{C}$ moving with velocity $10 \mathrm{~ms}^{-1}$ along the $X$-axis enters a region where a magnetic field of induction $B$ is along the $Y$ - axis and an electric field of magnitude $10^{4} \mathrm{~V} / \mathrm{m}$ is along the negative $\mathrm{Z}$-axis. If the charged particle continues moving along the $\mathrm{X}$-axis, the magnitude of $\mathrm{B}$ is

153706 Two electrons with initial speed $8 \times 10^{6} \mathrm{~m} / \mathrm{s}$ are released into a space with magnetic field $B$. The first electron is released along the $\mathrm{X}$-axis and it moves in a straight line. The second electron is shot from the origin along the $\mathbf{Y}$-axis and it moves in a circle that intersects the $\mathrm{Z}$-axis at: $=$ $+18 \mathrm{~cm}$. The magnitude and direction of $\vec{B}$ is $\left(\mathrm{m}_{\mathrm{e}}=\mathbf{9} \times 10^{-31} \mathrm{~kg}\right)$

153707 A beam of protons enters a uniform magnetic field of $0.314 \mathrm{~T}$ with a velocity $4 \times 10^{5} \mathrm{~ms}^{-1}$ in a direction making an angle $60^{\circ}$ with the direction of the magnetic field. The path of the beam is (mass of proton $=1.6 \times 10^{-27} \mathrm{~kg}$ )

153708 A proton is moving with a uniform velocity of $10^{6} \mathrm{~ms}^{-1}$ along the $\mathrm{Y}$-axis, under the joint action of a magnetic field along $Z$-axis and an electric field of magnitude $2 \times 10^{4} \mathrm{Vm}^{-1}$ along the negative $\mathrm{X}$-axis. If the electric field is switched off, the proton starts moving in a circle. The radius of the circle is nearly
$\text { (given : } \left.\frac{\mathrm{e}}{\mathrm{m}} \text { ratio for proton } \approx 10^{8} \mathrm{Ckg}^{-1}\right)$

153709 A particle of charge $-16 \times 10^{-18} \mathrm{C}$ moving with velocity $10 \mathrm{~ms}^{-1}$ along the $X$-axis enters a region where a magnetic field of induction $B$ is along the $Y$ - axis and an electric field of magnitude $10^{4} \mathrm{~V} / \mathrm{m}$ is along the negative $\mathrm{Z}$-axis. If the charged particle continues moving along the $\mathrm{X}$-axis, the magnitude of $\mathrm{B}$ is

153706 Two electrons with initial speed $8 \times 10^{6} \mathrm{~m} / \mathrm{s}$ are released into a space with magnetic field $B$. The first electron is released along the $\mathrm{X}$-axis and it moves in a straight line. The second electron is shot from the origin along the $\mathbf{Y}$-axis and it moves in a circle that intersects the $\mathrm{Z}$-axis at: $=$ $+18 \mathrm{~cm}$. The magnitude and direction of $\vec{B}$ is $\left(\mathrm{m}_{\mathrm{e}}=\mathbf{9} \times 10^{-31} \mathrm{~kg}\right)$

153707 A beam of protons enters a uniform magnetic field of $0.314 \mathrm{~T}$ with a velocity $4 \times 10^{5} \mathrm{~ms}^{-1}$ in a direction making an angle $60^{\circ}$ with the direction of the magnetic field. The path of the beam is (mass of proton $=1.6 \times 10^{-27} \mathrm{~kg}$ )

153708 A proton is moving with a uniform velocity of $10^{6} \mathrm{~ms}^{-1}$ along the $\mathrm{Y}$-axis, under the joint action of a magnetic field along $Z$-axis and an electric field of magnitude $2 \times 10^{4} \mathrm{Vm}^{-1}$ along the negative $\mathrm{X}$-axis. If the electric field is switched off, the proton starts moving in a circle. The radius of the circle is nearly
$\text { (given : } \left.\frac{\mathrm{e}}{\mathrm{m}} \text { ratio for proton } \approx 10^{8} \mathrm{Ckg}^{-1}\right)$

153709 A particle of charge $-16 \times 10^{-18} \mathrm{C}$ moving with velocity $10 \mathrm{~ms}^{-1}$ along the $X$-axis enters a region where a magnetic field of induction $B$ is along the $Y$ - axis and an electric field of magnitude $10^{4} \mathrm{~V} / \mathrm{m}$ is along the negative $\mathrm{Z}$-axis. If the charged particle continues moving along the $\mathrm{X}$-axis, the magnitude of $\mathrm{B}$ is

153706 Two electrons with initial speed $8 \times 10^{6} \mathrm{~m} / \mathrm{s}$ are released into a space with magnetic field $B$. The first electron is released along the $\mathrm{X}$-axis and it moves in a straight line. The second electron is shot from the origin along the $\mathbf{Y}$-axis and it moves in a circle that intersects the $\mathrm{Z}$-axis at: $=$ $+18 \mathrm{~cm}$. The magnitude and direction of $\vec{B}$ is $\left(\mathrm{m}_{\mathrm{e}}=\mathbf{9} \times 10^{-31} \mathrm{~kg}\right)$

153707 A beam of protons enters a uniform magnetic field of $0.314 \mathrm{~T}$ with a velocity $4 \times 10^{5} \mathrm{~ms}^{-1}$ in a direction making an angle $60^{\circ}$ with the direction of the magnetic field. The path of the beam is (mass of proton $=1.6 \times 10^{-27} \mathrm{~kg}$ )

153708 A proton is moving with a uniform velocity of $10^{6} \mathrm{~ms}^{-1}$ along the $\mathrm{Y}$-axis, under the joint action of a magnetic field along $Z$-axis and an electric field of magnitude $2 \times 10^{4} \mathrm{Vm}^{-1}$ along the negative $\mathrm{X}$-axis. If the electric field is switched off, the proton starts moving in a circle. The radius of the circle is nearly
$\text { (given : } \left.\frac{\mathrm{e}}{\mathrm{m}} \text { ratio for proton } \approx 10^{8} \mathrm{Ckg}^{-1}\right)$

153709 A particle of charge $-16 \times 10^{-18} \mathrm{C}$ moving with velocity $10 \mathrm{~ms}^{-1}$ along the $X$-axis enters a region where a magnetic field of induction $B$ is along the $Y$ - axis and an electric field of magnitude $10^{4} \mathrm{~V} / \mathrm{m}$ is along the negative $\mathrm{Z}$-axis. If the charged particle continues moving along the $\mathrm{X}$-axis, the magnitude of $\mathrm{B}$ is