IB Physics Mass and energy

A tutorial sheet of questions on mass and energy from topic E follows.

1. Can mass be "converted" into energy?
2. Can energy be "converted" into mass?
3. A Higgs boson has an approximate energy of 2 TeV. What is the mass associated with this energy? Give the answer in u.
4. A neutron has a mass of 1.00727 u. What is the rest mass of a neutron in GeV c^-2?
5. When a nuclear fission reaction occurs is mass "converted" into energy?
6. Where does the energy "come from" in a nuclear fission reaction?
7. Is mass "converted" into energy when an electron and a positron annihilate each other?
8. Is energy "converted" into mass when a gamma ray undergoes a par production reaction?
9. The rest mass of an electron is 0.5 MeV c^-2. What does this mean?
10. Is the binding energy of a nucleus positive or negative in sign?

IB Physics Gravitational fields

A tutorial sheet of questions on Topic D gravitational fields, HL, appears below.

1. Equipotential curves are drawn around a point mass. The difference in potential between the curves is constant. Do the equipotential curves become closer in distance, further in distance or the same separation as the distance from the point mass increases?
2. When the potential is maximum the field strength is zero. True of false?
3. When the field strength is maximum the potential is maximum. True or false?
4. Equal masses are placed at the vertices of an equilateral triangle. Sketch the gravitational field lines around the masses.
5. Explain why gravitational potential is negative in sign.
6. Two equal point masses M are placed a distance d apart. A point mass m is moved from infinity at a constant speed and is placed at the midpoint of the line joining the masses. Find the work done by an external force in moving the mass m from infinity to its final position. Does the work depend on the path taken?
7. A uniform solid sphere has a mass M and radius R. State the gravitational potential and field strength for (a) r >R (b) r < R. Sketch graphs for each case.
8. A uniform spherical shell has a mass M and radius R. State the gravitational potential and field strength for (a) r > R (b) r < R. Sketch graphs for each case.
9. Find the gravitational potential energy of a uniform solid sphere of mass M and radius R.
10. Find the gravitational potential energy of a uniform spherical shell of mass M and radius R.

IB Physics Rutherford model of the atom

A tutorial sheet of questions on aspects of the Rutherford model of the atom is given below.

1. The Rutherford model of the atom has protons and neutrons at the centre of an atom. True or false?
2. Marsden fired neutrons at a thin gold sheet and measured the number that passed through. True or false?
3. When alpha particles are scattered by a thin metal sheet the number detected at a scattering angle 𝜃 is (state true or false) a) proportional to the thickness of the foil b) proportional to the kinetic energy of the alpha particle c) proportional to the atomic number of the metal d) proportional to the cosine of 𝜃/2 squared.
4. Where are the electrons in the Rutherford model of the atom?
5. Sketch the path of an alpha particle of charge +2e as it passes close to a nucleus of charge +Ze. Assume that the mass of the nucleus is much greater than that of the alpha particle.
6. Sketch the path of an alpha particle of charge +2e as it passes close to a charge -Ze. Assume that the mass of the negative charge is much greater than that of the alpha particle.
7. What is the scattering statistic in this experiment?

IB Physics Magnetic fields

A tutorial sheet on topic D magnetic fields appears below.

1. What produces a magnetic field?
2. Two parallel wires carry equal currents in the same direction. Sketch a graph showing the magnetic field strength on a line through each wire perpendiculr to the wires.
3. Sketch the magnetic field lines in the plane perpendicular to each wire.
4. Three parallel wires carry equal currents I. The wires are at the vertces of an equilateral triangle of side d. Find the magnetic force per unit length acting on each wire.

IB Physics Simple harmonic motion

A tutorial sheet of simple harmonic motion (SHM) questions for IB SL and HL appears below.

1. A simple pendulum always swings in SHM. True or false?
2. A simple pendulum has a mass on the end of a string of length L. The mass hangs at rest. It is given a small horizontal velocity u. If the initial speed is doubled, which case, high initial speed or low initial speed, has the greater a) period of oscillation, b) energy, c) tension in the string.
3. A particle moves in SHM of period 6.00 s and amplitude 12.0 cm. Find the least time taken by the particle to move from x = +8.00 cm to x = +4.00 cm.

IB Physics Photons

A tutorial sheet of questions on photons is given below.

1. Define the term photon.
2. Does a photon have a wavelength?
3. Does a photon have an amplitude?
4. Does a beam of photons have an intensity?
5. Can photons be polarised?
6. What is the difference between an electron neutrino and a photon?

IB Physics Angular momentum

A tutorial sheet of questions on angular momentum is given below.

1. Define the angular momentum of a particle about a point.
2. Define the angular momentum of a rigid body about its axis of rotation.
3. State the condition for the angular momentum of a particle about a point to be conserved.
4. Linear momentum is always parallel to the linear velocity...true or false?
5. Angular momentum is always parallel to the angular velocity...true of false.

IB Physics Rolling cylinders

A tutorial sheet of questions on rolling cylinders is given below.

1. Do ALL cylinders roll on an inclined plane with the same acceleration?
2. Does a cylinder always roll when it is released from rest on a rough inclined plane?
3. In a dynamics sense, what is the definition of rolling?
4. The coefficient of static friction between two surfaces is μ. Find the minimum angle of elevation of an inclined plane to allow a cylinder to roll down the incline.
5. Why does the coefficient of static friction appear in rolling questions?
6. A uniform pipe has a mass M and inner and outer radii a and b respectively. Find the moment of inertia of the pipe about an axis through its centre parallel to the length of the pipe.

IB Physics Interference

A tutorial sheet of some interference concepts in SL and HL is given below.

1. Laser light is directed on two slits of width b and separation d. The interference pattern is observed on a screen at a distance D from the slits. How does the intensity pattern on the screen change when one of the slits is covered?
2. A telescope can just resolve each star in a double star system when the observation is made in yellow light. In which light will the star images be not resolved, red light or blue light?
3. Two synchronous sources are 0.50 m apart. Each source produces sound waves of wavelength 2.0 m. A microphone is initially at a distance of 10.0 m from each source. The intensity reading on the microphone is I. Draw a graph showing the intensity reading on the microphone as it is moved towards the sorrces on the bisector of the line joining the sources.

IB Physics Electric current

A tutorial sheet of questions on electric current is given below.

1. State the definition of electric current.
2. The ampere is a fundamental unit. What does a current of 1 A mean?
3. Every second 100 electrons pass a point moving to the left. What is the current?
4. Every minute 1000 electrons pass a point moving to the right. In the same time interval 1000 protons pass this point moving at the same rate to the right. The charges do not interact. a) What is the current at this point? b) What net charge passes this point in this time interval?

IB Physics Magnetic Force Between Two Currents

A tutorial sheet of questions exploring the magnetic force between two currents follows.

1. A wire carries a current. What is the net charge on the wire?
2. A wire carries a current. Where does the charge flow on the wire? Inside or on its surface?
3. Two parallel wires carry currents in the same direction. Describe the force/s acting on each wire.
4. Two protons are initially moving with the same velocity parallel to each other. Describe the force/s acting on each proton.

IB Physics HL Resonance

A tutorial sheet of resonance questions from the Engineering Physics option is given below.

1. An oscillator is subject to no damping. Describe its motion if its natural frequency is 2𝜔 and the driving frequency is 𝜔.
2. An oscillator undergoes damped oscillations. Is the frequency of the damped oscillations the same as the undamped oscillations?
3. An oscillator has a natural frequency 𝜔 and is subject to a damping acceleration that is proportional to its velocity with a proportionality constant 2k. Write down the condition for (a) damped oscillations (b) critically damped oscillations (c) overdamping.
4. An oscillator has damping. When the damping is increased does the frequency at which the maximum forced oscillations occur increase or decrease? Give a reason.

IB Physics Resistors and Capacitors

A tutorial sheet of resistor and capacitor questions follows.

1. An uncharged 6.0 mF capacitor is placed in series with a battery of emf 12 V. Find the charge on the capacitor after 6.0 min.
2. A 20 pC capacitor is connected in series to a 20Ω resistor. The initial charge on the capacitor is 2.0 mC. Find the charge on the capacitor after 20.0 s.
3. A battery of emf 12.0 V and internal resistance 2.0 Ω is used to charge a 600 pF capacitor for 5.0 min. The capacitor is initially uncharged. Find (a) the work done by the battery in the 5.0 min, (b) the energy stored in the capacitor after 5.0 min.

IB Physics Viscosity

A tutorial sheet on viscosity is given below.

1. Is viscosity a force?
2. What is the cause of viscosity?
3. State the SI unit for viscosity.
4. A small sphere of radius r is falling vertically in a fluid of viscosity 𝛈 and density 𝜌. Find an expression for the terminal speed of the sphere.
5. A viscous fluid flows steadily through a horizontal pipe. Does the pressure exerted by the fluid change along the pipe?

IB HL Physics Time Dilation

The new HL Physics course includes special relativity for all students. Below is a tutorial sheet on time dilation.

1. Do moving clocks run slower?
2. Define proper time.
3. A particle has a lifetime of 2.0 µs in its rest frame. The particle moves at 0.8c relative to a laboratory. Find the lifetime of the particle according to an observer in the laboratory reference frame.
4. Two detectors in a laboratory are 20.0 cm apart. A particle moving at a constant speed of 0.9 c relative to the laboratory passes through the detectors. What is the time of passge between the detectors as measured in the reference frame of the particle?

IB Physics EMF of a cell

Which of the following is/are correct regarding the emf of a cell?

1. The voltage of the battery.
2. The potential difference across the terminals of the cell when zero current passes through it.
3. The work done in moving unit charge through the cell.
4. The work done in moving unit charge around the circuit.
5. The chemical energy changed to thermal energy when unit charge moves through the cell.
6. The power per unit current passing through the cell.

IB HL Physics Electric Field in a Moving Conductor

A conductor moves in a magnetic field. Is the electric field in the conductor zero? A tutorial sheet follows.

1. State Ohm's law in terms of electric field (E) and current density (J).
2. A current flows through a stationary conductor that obeys Ohm's law. Is there an electric field inside the conductor? Outside of the conductor?
3. A straight metal rod of length L is a perfect conductor (zero resistance). The rod moves at a constant velocity v along the x-axis through a uniform magnetic field B along the z-axis. The length of the rod is along the y-axis. Find the electric field in the rod in the (a) reference frame of the laboratory, (b) reference frame of the rod.
4. In the previous question find the force acting on a charge q in the rod relative to the reference frame of the rod.
5. In question 3 the rod has a constant non-zero resistance. Find the force on a charge q in the rod relative to the reference frame of the rod.

IB Physics Work Done on a Moving Charge in a Magnetic field

A common question is finding the work done on a charge as it moves in a magnetic field. Is it always zero? A tutorial sheet of questions investigates this concept.

1. A constant, uniform magnetic field B acts along the x-axis. A charge q enters the field at a velocity v at an angle 𝜃 to the x-axis. Is work done on the moving charge?
2. A constant current flows along a long straight wire that is along the x-axis. At a certain instant a charge q is moving along the x-axis at a speed v towards the wire. Is work done on the charge?
3. A magnetic field increases at a rate proportional to the time, B = kt, and its direction is parallel to the x-axis. Does the magnetic field do work on the moving charge in question 1? Does the associated electric field do work on the moving charge?

IB Physics Collision rate in an ideal gas

A tutorial sheet on particle collisions in an ideal gas is given below.

1. The temperature of an ideal gas is doubled, the volume of the container being kept constant. Describe the change in the rate of collision of the particles with the walls of the container.
2. The pressure of an ideal gas is tripled, the volume being kept constant. Describe the change in the rate of collision of the particles with the walls of the container.
3. The volume of an ideal gas is reduced by one-quarter, the temperature of the gas being kept constant. Describe the change in the rate of collision of the particles with the walls of the container.
4. At what conditions does a real gas behave closest to an ideal gas?

IB Physics Gravitational field strength

A tutorial sheet of questions on gravitational field strength is below.

1. The mass of the Moon is 1/81.3 that of the Earth. Assuming a model in which the bodies are considered to be point particles at rest, find the location of the point in space where the resultant gravitational field is zero.
2. In question 1 consider of model in which the Moon moves in a circular path about the centre of the Earth. Does the zero field point move closer, stay the same or move further away from the Earth? Calculate its position assuming an orbital period of 27.32 days.
3. In question 1 is/are there points inside the Earth or the Moon where the resultant gravitational field strength is zero?