Fields

If the mass of the Earth were to double without changing its radius, the gravitational field strength at its surface would:

Which of the following statements about gravitational potential is true?

If the radius of an orbit is increased, the orbital speed of a satellite:

For a satellite in a stable circular orbit, the centripetal force is provided by:

Two point masses of $4M$ and $M$ are separated by a distance $d$ in a vacuum. Point $X$ is the unique position on the line connecting the two masses where the resultant gravitational field strength is zero. What is the total gravitational potential at point $X$ due to these two masses?

The gravitational field strength at the surface of a moon is $1.6 \text{ N kg}^{-1}$. If the radius of the moon is $1.7 \times 10^6 \text{ m}$, what is the gravitational potential at its surface?

A satellite orbits a planet at a distance $r$ from the center. If the satellite's mass is doubled but it stays in the same orbit, its orbital speed will:

A mass $M$ is split into two parts, $m$ and $M-m$. What is the ratio $m/M$ that maximizes the gravitational force between the two parts for a fixed separation?

Which of the following is true for a satellite in an elliptical orbit?

The orbital speed of a satellite in a circular orbit just above the surface of a planet is $v$. What is the escape velocity from the same planet?

A charge of $1.0\,nC$ is equivalent to how many Coulombs?

What is the force experienced by a neutral atom in a uniform electric field?

Which of the following is true for the electric field lines of two equal positive charges placed near each other?

The unit $eV$ (electronvolt) is a unit of:

Which of the following is equivalent to $1\,Volt$?

The force on a charge $q$ in an electric field $E$ is $F$. If a second charge $-2q$ is placed in the same field, the force it experiences is:

Two equal but opposite charges are placed at the corners of the base of an equilateral triangle. What is the direction of the net electric field at the third corner (the apex)?

An electron moves in a circular orbit around a fixed proton. If the radius of the orbit is $r$, what is the total energy of the electron?

A uniform electric field is $E = 100 N/C$ in the $+x$ direction. If the potential at $x = 2 m$ is $50 V$, what is the potential at $x = 5 m$?

A proton is moving at $3.0 \times 10^5 m/s$ towards another stationary proton. What is the distance of closest approach?

Which property determines the direction of the magnetic field produced by a solenoid?

When the velocity of a charged particle is parallel to the magnetic field, the radius of its path is:

Which of the following is true for an ideal solenoid?

Magnetic flux density is another name for which quantity?

A current $I$ flows through a conductor of length $L$ in a magnetic field $B$. If the angle between $I$ and $B$ is $\theta$, the force is $F$. If $\theta$ is changed from $30^{\circ}$ to $90^{\circ}$, the force increases by a factor of:

An ion source emits ions of different masses but same charge into a mass spectrometer. If they are accelerated by the same voltage and then enter a uniform $B$-field, how does the radius $R$ relate to the mass $m$?

A proton and an electron enter a uniform magnetic field with the same kinetic energy. Which particle will follow a path with a smaller radius of curvature?

An electron moves in a circle of radius $r$ in a uniform magnetic field $B$. If the magnetic field is slowly increased, what happens to the radius $r$ and the kinetic energy $K$ of the electron?

A particle with charge $q$ is at rest in a region with a uniform magnetic field $B$. At $t=0$, a uniform electric field $E$ is turned on perpendicular to $B$. What is the maximum speed reached by the particle?

A solenoid of length $0.5$ m and $500$ turns carries a current of $2.0$ A. What is the magnetic flux through a small 10-turn coil of area $1.0 \times 10^{-4}$ m$^2$ placed at the center of the solenoid with its plane perpendicular to the solenoid axis?

When comparing two points in an electric field, the point at the higher potential is the one where a:

If electric field lines are parallel and equally spaced, the field is:

To find the work done in moving a charge $q$ between potentials $V_1$ and $V_2$, use the formula:

Which of the following is true for an ideal conductor in electrostatic equilibrium?

The diagram shows three equipotential surfaces in an electric field. Surface 1 is at a potential of $15 \text{ V}$, Surface 2 is at $10 \text{ V}$, and Surface 3 is at $5 \text{ V}$. A positive test charge $+q$ is moved from point $X$ (on Surface 1) to point $Y$ (on Surface 2), and then to point $Z$ (also on Surface 2). Which of the following correctly describes the work done by the electric field on the charge during the displacements $X \to Y$ and $Y \to Z$?

If a mass is moved between two points in a gravitational field and the net work done is zero, which of the following must be true?

Field lines between two parallel plates are straight and parallel. This indicates that:

In a binary star system, at the point between the stars where the net gravitational field is zero (Lagrange point L1), the gravitational potential is:

If the electric potential $V$ in a region is $V(x) = 10/x$, what is the electric field strength $E$ at $x = 2 \, \text{m}$?

An electron and a proton are placed in a uniform electric field. Which of the following is true?

1. Electromagnetic Induction (HL): practice question 1 for Fields?

1. Electromagnetic Induction (HL): practice question 2 for Fields?

1. Electromagnetic Induction (HL): practice question 3 for Fields?

1. Electromagnetic Induction (HL): practice question 4 for Fields?

1. Electromagnetic Induction (HL): practice question 5 for Fields?

1. Electromagnetic Induction (HL): practice question 6 for Fields?

1. Electromagnetic Induction (HL): practice question 7 for Fields?

1. Electromagnetic Induction (HL): practice question 8 for Fields?

1. Electromagnetic Induction (HL): practice question 9 for Fields?

1. Electromagnetic Induction (HL): practice question 10 for Fields?

Which path will a stationary positive charge take when released in a non-uniform electric field (neglecting gravity)?

If you double both the magnitude of two point charges and double the distance between them, what happens to the electrostatic force?

In the context of electrostatics, what does 'grounding' an object typically do?

What is the net charge of an atom that has gained two electrons?

The potential at a point is $V$. The work done to bring a charge $q$ from infinity to that point is $W$. What is the relationship?

What is the direction of the electric field at the center of a square with charges $+q, -q, +q, -q$ arranged clockwise at the corners?

An electron is released from rest in a uniform electric field. The graph of its speed $v$ against time $t$ would be a:

A dipole with dipole moment $p$ is rotated from its equilibrium position (parallel to field $E$) to a position anti-parallel to the field. What is the work done by the external agent?

The electric field strength $E$ near an infinitely large charged conducting plate with surface charge density $\sigma$ is:

Two identical metallic spheres carry charges $+10 \mu C$ and $-20 \mu C$. They are brought into contact and then separated to their original positions. What is the ratio of the magnitude of the final force to the initial force?

If the electric potential at a point is $V$, the potential energy of a charge $q$ at that point is:

Which of the following diagrams correctly shows the electric field around a single isolated positive point charge?

A magnetic field is created by:

Potential difference is defined as the work done per unit:

A small sphere of mass $m$ and charge $q$ is suspended from a ceiling by an insulating thread of negligible mass. A uniform horizontal electric field of strength $E$ is applied, causing the sphere to reach equilibrium at an angle $\theta$ relative to the vertical. Which of the following expressions correctly relates these variables?

Which physical quantity is a vector?

The direction of the magnetic field lines outside a bar magnet is:

A current $I$ is flowing in a wire. If the wire is placed in a magnetic field $B$, under what condition is the force on the wire zero?

An electron enters a region of uniform magnetic field $B$ at an angle of $90^{\circ}$. The work done by the magnetic field on the electron after one complete revolution is:

Two charges $+q$ and $-q$ are placed at a distance $2d$ apart. The electric field at the midpoint is:

A $1.5 \, m$ wire carries a current of $10 \, A$ in a $0.2 \, T$ field at an angle of $30^\circ$ to the field. What is the force on the wire?

The direction of the magnetic field at any point is given by the direction that the:

A charge moves in a circular path in a magnetic field. If the magnetic field strength is doubled, the radius of the path will:

An electron and a proton are in the same uniform electric field. Which particle experiences the greater magnitude of acceleration?

A $20 \text{ cm}$ wire carrying a $5.0 \text{ A}$ current is perpendicular to a $0.50 \text{ T}$ magnetic field. The force on the wire is:

Which of the following is true for a charged particle moving in a uniform magnetic field?

A magnetic force $F$ acts on a wire of length $L$ carrying current $I$. If the magnetic field strength is tripled, the force becomes:

A particle with charge $Q$ is moving in a uniform magnetic field $B$. If the particle's speed is $v$ and the radius of its circular path is $r$, what is the magnetic flux density $B$ in terms of the particle's momentum $p$?

A magnetic field is directed into the page. A positive charge moves from left to right in the plane of the page. What is the direction of the force?

Two parallel plates are separated by distance $d$ and have a potential difference $V$. An ion of charge $+q$ and mass $m$ starts from rest at the positive plate. What is its speed when it has covered a distance $d/2$?

1. Induction (HL): practice question 1 for Fields?

1. Induction (HL): practice question 2 for Fields?

1. Induction (HL): practice question 3 for Fields?

1. Induction (HL): practice question 4 for Fields?

1. Induction (HL): practice question 5 for Fields?

1. Induction (HL): practice question 6 for Fields?

1. Induction (HL): practice question 7 for Fields?

1. Induction (HL): practice question 8 for Fields?

1. Induction (HL): practice question 9 for Fields?

1. Induction (HL): practice question 10 for Fields?