Magnetic Force on Moving Charge

Q.

A particle enters a magnetic field at right angles as shown.

The direction of force acting on the particle is into the page. The charged particle is a/an:

1. Proton
2. Neutron
3. Electron
4. Alpha particle

Q.

A charged particle moves in a clockwise direction in a magnetic field which is perpendicular to the plane of paper directed downwards. What is the nature of charged particle ?

Q.

When a positively charged particle enters a uniform magnetic field with uniform velocity, then the trajectory can be
(i) A circle
(ii) A straight line
(iii) A helix

1. Only (i)

2. (i) or (ii)

3. (i) or (iii)

4. Anyone of (i), (ii), or (iii)

Q. The magnetic force experienced by an electron moving with a velocity of $2775km{s}^{-1}$ at an angle of ${30}^{\circ }$ to a magentic field is $7.336\times {10}^{-14}N$. What is the strength of the magnetic field (in Tesla)? Given, the electron charge, $e=1.6\times {10}^{-19}C$

1. $1.28$
2. $0.33$
3. $0.26$
4. $1.09$

Q. An electron is moving perpendicular to a magnetic field of strength $0.55T$. Calculate the approximate time period of the electron in the field. Take the mass of the electron $m_e=9.1\times {10}^{-31}kg$ and its charge $e=1.6\times {10}^{-19}C$.

1. $44\times {10}^{-3}s$
2. $65\times {10}^{-12}s$
3. $37\times {10}^{-9}s$
4. $52\times {10}^{-12}s$

Q. A charge moves in a circle perpendicular to a magnetic field. The time period of revolution is independent of

1. Magnetic field
2. Mass of the particle
3. Charge
4. Velocity of the particle

Q. An electron is moving perpendicular to a magnetic field of strength 10 tesla with a velocity of 2200 $kmse{c}^{-1}$. Calculate the radius of its path. (The mass of the electron $m=9.1\times {10}^{-31}kg$ and its charge $e$ = 1.6 $\times {10}^{-19}C$ )

1. 2.50 $\times {10}^{-3}m$
2. 1.42 $\times {10}^{-2}m$
3. 1.25 $\times {10}^{-6}m$
4. 1.78 $\times {10}^{-3}m$

Q. name the force responsible to cause acceleration in uniform circular motion.

Q. A current carrying loop is placed near a long straight wire which also conducts a current. The direction of currents are shown in the figure, then which of the following options are correct?

97

1. The wire is repelled from the loop
2. The wire does not experience any force
3. The wire is attracted towards the loop
4. The wire will have attraction or repulsion depending on the magnitudes of the currents

Q. Like poles repel and unlike poles attract each other.

1. True
2. False

Q. A laboratory has very strong magnetic field upwards, i.e. towards the ceiling. An electron gun is fired towards a wall. The electron will:

1. Hit the other wall along the same line.
2. Hit the ceiling.
3. Hit the ground.
4. Hit the wall on the left side of the shooter.

Q. Which of the following objects can experience a force in the magnetic field?

1. Plastic
2. Moving charge
3. Wood
4. Glass

Q. A charged particle enters a non-uniform magnetic field varrying from point to point both in magnitude and direction with a certain initial velocity what do you say about it. Find velocity of particle where it leaves field.

Q. Below a negatively charged particle is pictured moving north east through a magnetic field that points straight up. What is the direction of the force on the negatively charged particle at the moment it is pictured?

1. northeast
2. southeast
3. southwest
4. northwest
5. up

Q. Which of the following property of a proton can change while it moves freely in a uniform magnetic field?

1. Mass
2. Speed
3. Velocity
4. Charge

Q. A charged particle is moving at a certain speed perpendicular to a magnetic field. What would be the shape of the path of the particle in the field?

1. Linear
2. Elliptical
3. Circular
4. Irregular

Q. A positively charged particle moving due east enters a region of uniform magnetic field directed vertically upwards. The particle will_______.

1. get deflected in opposite direction.
2. move in a circular path.
3. get deflected in vertically upward direction.
4. get deflected in downward direction only.