Physics HL

Question 1 

Newton’s second law of motion states that:

1. The net force acting on a body is equal to the product of its mass and velocity.
2. When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.
3. The net force acting on a body is proportional to the momentum of the body.
4. The rate of change of momentum of a body is equal to the net force acting on the body.

Question 2 

A small object is attached to a string and is made to move in a horizontal circle.

Which of the following free-body diagrams correctly shows the forces that act on the object?

Question 3 

A speedboat starts from rest and accelerates at 5.0 m s^{-2}. What is the velocity of the speedboat after it has travelled a distance of 10 m?

1. 2.5 m s^{-1}
2. 5.0 m s^{-1}
3. 10 m s^{-1}
4. 50 m s^{-1}

Question 4 

Which of the following statements is true about an inertial reference frame?

1. The laws of physics depend on the velocity of the reference frame.
2. Newton’s laws of motion depend on the velocity of the reference frame.
3. The speed of light relative to an observer in the reference frame depends on the motion of the light source relative to the observer.
4. The speed of the reference frame is constant.

Question 5 

Which of the following equations is the rotational equivalent of Newton’s second law of motion for an object of constant mass?

1. \textup{force = mass} \times \textup{angular acceleration}
2. \textup{force = moment of inertia} \times \textup{angular acceleration}
3. \textup{torque = mass} \times \textup{angular acceleration}
4. \textup{torque = moment of inertia} \times \textup{angular acceleration}

Question 6 

An object moves is a circle at a constant speed of 6.0 m s^{-1}. The radius of the circle is 2.0 m. What is the angular speed of the object?

1. 1.5 rad s^{-1}
2. 3.0 rad s^{-1}
3. 12 rad s^{-1}
4. 24 rad s^{-1}

Question 7

The SI unit combination of energy density is:

1. J m^{3}
2. J m^{-3}
3. J kg
4. J kg^{-1}

Question 8 

Two forces act on an object as shown on the diagram.

Which of the following vectors shows the direction of the net force acting on the object?

Question 9 

The diagram shows a solid cylinder that is rolling down a slope without slipping. 

The three forces that act on the cylinder are the weight, the normal force, and the frictional force between the cylinder and the slope. 

Which of these forces provides a torque about the axis of the cylinder?

1. The weight
2. The normal force
3. The frictional force
4. None of them

Question 10 

A graph shows how the velocity of an object varies with time. What does the gradient of the graph represent?

1. The displacement of the object
2. The acceleration of the object
3. The momentum of the object
4. It does not represent a physical quantity

Question 11 

An object is moving at constant speed. Which graph shows the variation of E, its kinetic energy, with s, its displacement?

Question 12 

A sphere of radius 2.0\; \textup{m} is rotating about its diameter with an angular speed of 5.0\; \textup{rad\,s}^{-1}. The moment of inertia for the sphere is I = \frac{2}{5}mr^{2}, where m is the mass and r is the radius of the sphere.

Given that the rotational kinetic energy of the sphere is 50\; \textup{J}, what is the mass of the sphere?

1. 2.5\; \textup{kg}
2. 5.0\; \textup{kg}
3. 7.5\; \textup{kg}
4. 10\; \textup{kg}

Question 13 

A small sphere is falling through oil at constant speed.

Which of the following free-body diagrams correctly shows the forces that act on the sphere?

Question 14 

A train is moving in a straight line to the left at a constant speed of 6.0\;\textup{m\,s}^{-1} relative to the ground. A person on the train walks to the right at a constant speed of 1.5\;\textup{m\,s}^{-1}.

What is the speed of the person relative to the ground?

1. 1.5\;\textup{m\,s}^{-1}
2. 4.5\;\textup{m\,s}^{-1}
3. 6.0\;\textup{m\,s}^{-1}
4. 7.5\;\textup{m\,s}^{-1}

Question 15 

A thermally isolated container has 10 kg of ice. The specific latent heat of fusion of ice is 0.336 MJ kg^{-1}. How much energy must be supplied to the ice to completely melt it, without changing its temperature? 

1. 0.0336 MJ
2. 0.336 MJ
3. 3.36 MJ
4. 33.6 MJ

Question 16 

The graph shows how the pressure of an ideal gas varies with its volume during change AB.

Change AB is

1. adiabatic.
2. isothermal.
3. isovolumetric.
4. isobaric.

Question 17 

The resistance of an aluminium wire of length L and radius r is R. What will be the resistance when both the length and the radius are doubled?

1. 0.5R
2. R
3. 2R
4. 4R

Question 18 

The density of a metal cube with side length L and mass M is \rho.

What is the density of a metal cube with side length \frac{L}{2} and mass \frac{M}{4}?

1. \frac{\rho}{4}
2. 4 \rho
3. \frac{\rho}{2}
4. 2 \rho

Question 19 

Containers A and B contain the same substance at the same temperature. In container A the substance is in the gas state. In container B the substance is in the liquid state. The average kinetic energy of the molecules in container A is E_{A} and the average kinetic energy of the molecules in container B is E_{B}. What is true about E_{A} and E_{B}?   

1. Based on the information provided, the relationship between E_{A} and E_{B} cannot be determined.
2. E_{A}>E_{B}
3. E_{A}<E_{B}
4. E_{A}=E_{B}

Question 20 

A heat engine wastes 4000\: \textup{J} of energy during a cycle. The work done by the heat engine during the same cycle is 1000\: \textup{J}.

What is the heat engine’s efficiency?

1. 0.20 
2. 0.25 
3. 0.75 
4. 0.80

Question 21 

A student wants to connect an ammeter and a voltmeter to measure the current through and the potential difference across a resistor. How should the ammeter and the voltmeter be connected to the resistor?

Question 22 

Water is heated from 40 ^{o}C to 50 ^{o}C in a thermally isolated container. The total energy supplied to the water is 84000 J. The specific heat capacity of water is 4200 J kg^{-1} K^{-1}. What is the mass of the water?

1. 0.2 kg
2. 0.5 kg
3. 2.0 kg
4. 5.0 kg

Question 23 

Which of the following is not an assumption of the kinetic model of ideal gases?

1. The volume of each molecule is negligible compared to the total volume of the gas.
2. Intermolecular forces between the particles are negligible.
3. The duration of collisions is negligible compared to the time between collisions.
4. The change in the velocity of the molecules is negligible during collisions with the container wall.

Question 24 

For a Carnot engine with an efficiency of 0.50,  T_{\textup{c}} = 100\:\textup{K}, where T_{\textup{c}} is the temperature at which heat leaves the engine. 

What is T_{\textup{h}}, the temperature at which heat is transferred into the engine?

1. 400\:\textup{K}
2. 200\:\textup{K}
3. 100\:\textup{K}
4. 50\:\textup{K}

Question 25 

The power supplied by a battery per unit current from the battery is a definition of:

1. Potential difference
2. Electromotive force
3. Internal resistance
4. Ohm’s law

Question 26 

The rate of global warming will most likely be increased by:

1. replacing coal-based power stations by nuclear power stations.
2. reforestation.
3. using natural gas instead of oil.
4. decreasing the use of renewable energy sources.

Question 27 

A monatomic real gas can behave very similarly to an ideal gas under certain conditions. Which of the following is one of these conditions?

1. Low pressure
2. Low temperature
3. High pressure
4. High density

Question 28 

A temperature of 58 ^{o}C is equal to:

1. -215 K
2. 215 K
3. -331 K
4. 331 K

Question 29 

A substance turns from a liquid into a solid. The temperature of the substance does not change during the process. Which of the following statements is true about the process?

1. Energy is supplied to the substance.
2. The total internal energy of the system decreases.
3. The kinetic energy of the molecules in the substance decreases.
4. The intermolecular potential energy of the substance is unchanged. 

Question 30 

Which of the following lists three greenhouse gases?

1. Carbon dioxide, methane, oxygen
2. Methane, water vapour, nitrous oxide
3. Water vapour, oxygen, carbon dioxide
4. Nitrous oxide, nitrogen, methane

Question 31 

Which of the following shows colours of visible light in increasing order of wavelength?

1. red, green, violet
2. green, red, violet
3. violet, green, red
4. violet, red, green

Question 32 

A pendulum oscillates with simple harmonic motion (SHM). The length of the pendulum is 10 m and the gravitational acceleration is 10 m s^{-2}.

What is the period of the pendulum?

1. \pi 
2. 2\pi 
3. 4\pi 
4. 8\pi 

Question 33 

Two pulses travel towards each other as shown on the diagram. 

Which one of the following diagrams shows a possible configuration when the two pulses meet?

Question 34 

A train sounds its horn while moving away from a stationary observer. The frequency of the observed sound is different from the frequency of the emitted sound, because:

1. The speed of sound relative to the observer has increased.
2. The speed of sound relative to the observer has decreased.
3. The wavelength detected by the observer is longer than the emitted wavelength.
4. The wavelength detected by the observer is shorter than the emitted wavelength.

Question 35 

Three statements about single-slit diffraction are:

I. The angular width of the central maximum is twice that of the secondary maxima.

II. The intensity of the first diffraction maximum is approximately 5 % of the intensity of the central maximum.

III. When white light is incident on the slit, each  secondary maxima has the colours of the visible part of the electromagnetic spectrum.  

Which of these statements are correct?

1. I and II only
2. I and III only
3. II and III only
4. I, II and III

Question 36 

A particle oscillates with simple harmonic motion (SHM) of amplitude A. When the displacement of the particle is \frac{2A}{3}, its kinetic energy is E. What is the kinetic energy of the object when its displacement is A?

1. zero
2. \frac{9E}{5}
3. \frac{9E}{4}
4. 9E

Question 37 

When a transverse wave travels through a medium, which of the following is true about the direction of propagation and the energy transfer of the wave in relation to the displacement of the medium?

Question 38 

The Doppler effect:

1. Occurs for light waves only.
2. Occurs for sound waves only.
3. Occurs both for light waves and sound waves.
4. Occurs neither for light nor for sound waves.

Question 39 

An object on a spring oscillates with simple harmonic motion (SHM) on Earth. Which of the following statements is true about the period of this system?

1. It is influenced by the length of the spring.
2. It is influenced by the spring constant.
3. It is independent of the mass of the object.
4. It will increase when the system is taken to the Moon.

Question 40 

Which statement correctly describes a difference between single-slit diffraction and double-slit interference?

1. A single-slit diffraction pattern is only observed when monochromatic light passes through a slit.
2. The double-slit interference pattern is not influenced by the width of the slits.
3. The appearance of the single-slit diffraction pattern only depends on the wavelength of the incident light.
4.  In a single-slit diffraction pattern, the intensity of the first secondary maximum is only about 5% of the principal maximum, while in a double-slit interference pattern it is much higher.

Question 41 

What is the direction of a wavefront relative to a ray for an electromagnetic wave and for a sound wave?

Question 42 

The distance between two adjacent nodes on a standing wave is 4 cm. What is the wavelength of the wave?

1. 1 cm
2. 2 cm
3. 4 cm
4. 8 cm

Question 44 

A particle is held at point Y, located at the same distance from the centres of two large spherical masses. The particle is not influenced by any other masses.

What happens when the particle is released?

1. It moves to point X and comes to rest there.
2. It remains at point Y.
3. It oscillates about point X.
4. It moves vertically upwards.

Question 45 

The direction of the current induced in a conductor is such as to oppose the change that created the current. This statement is:

1. only true for alternating currents.
2. only true for direct currents.
3. equivalent to Lenz’s law.
4. equivalent to Faraday’s law of induction.

Question 46 

What is true about an isolated, hollow, charged metal sphere?

1. The electric field strength inside the sphere is zero.
2. The electric potential inside the sphere is zero. 
3. The electric field strength at the surface of the sphere is zero.
4. The electric potential at the surface of the sphere is zero.

Question 47 

Two parallel, straight wires carry currents in opposite directions as shown on the diagram.

Which of the following statements is correct about the wires?

1. The magnitude of the forces exerted by the wires on each other is the same. The forces are repulsive.
2. The magnitude of the forces exerted by the wires on each other is the same. The forces are attractive.
3. The force exerted by wire A on wire B is smaller than the force exerted by wire B on wire A. The force is repulsive.
4. The force exerted by wire A on wire B is smaller than the force exerted by wire B on wire A. The force is attractive.

Question 48 

A planet is orbiting a star in a circular orbit. Which of the following statements about the forces acting in this situation is incorrect?

1. The magnitude of the gravitational force that acts on the planet is \frac{mv^{2}}{r} where m is the mass of the star, v is the orbital speed of the planet, and r is the distance between the centre of the star and the centre of the planet.
2. The direction of the planet’s acceleration is the same as the direction of the resultant force on the planet.  
3. The resultant force on the planet is pointing towards the centre of the star.
4. The magnitude of the force exerted by the planet on the star is the same as the magnitude of the force exerted by the star on the planet.

Question 49 

Which of the following quantities is needed in order to calculate the orbital speed of a satellite about a planet?

1. The mass of the satellite
2. The mass of the planet
3. The distance of the satellite from the surface of the planet
4. The radius of the planet

Question 50 

One electronvolt is equivalent to:

1. 1.6 \times 10^{-19} N
2. 1.6 \times 10^{-19} W
3. 1.6 \times 10^{-19} V
4. 1.6 \times 10^{-19} J

Question 51 

A proton is held at rest between two parallel, charged plates. The gravitational force acting on the proton is negligible. 

In which direction will the proton move when released?

1. Left
2. Right
3. Downwards
4. Upwards

Question 52 

The force acting per unit mass experienced by a small point mass at a given point is:

1. Newton’s law of universal gravitation.
2. Newton’s third law.
3. the definition of the centripetal force.
4. the definition of gravitational field strength.

Question 53 

In two dimensions, electric field lines and equipotentials:

1. are parallel. 
2. are equidistant.
3. are perpendicular.
4. do not intersect.

Question 54 

Phobos is one of the moons that orbits Mars. Newton’s universal law of gravitation can be applied to calculate the force between Phobos and Mars. Which one of the following conditions enables this calculation?

1. Phobos and Mars can be considered as point masses.
2. The distance between Phobos and Mars is large enough.
3. Phobos and Mars both have a large volume.
4. Phobos has a circular orbit around Mars.

Question 55 

On the graph that shows how average binding energy per nucleon varies with nucleon number, the most stable elements can be found:

1. around the minimum point of the graph.
2. around the maximum point of the graph.
3. near the horizontal axis intercept.
4. near the vertical axis intercept.

Question 56 

What is the main source of energy in stars?

1. Nuclear fusion
2. Nuclear fission
3. The burning of fossil fuels at high temperatures
4. Radioactive decay

Question 57 

The half-life of a radioactive isotope is two days. If the initial activity of a pure sample of this isotope is 600 Bq, what will be the activity of the sample after 8 days?

1. 0
2. 19 Bq
3. 38 Bq
4. 150 Bq

Question 58 

Which of the following is true about the photoelectric effect?

1. The work function of the surface from which the electrons are emitted must be larger than the energy of the incident photons.
2. The frequency of the incident photons must be in the visible range of the electromagnetic spectrum.
3. The kinetic energy of the emitted electrons is inversely proportional to the frequency of the incident light.
4. Electrons are emitted instantaneously from the metal surface.

Question 59 

The existence of atomic energy levels is supported by:

1. evidence from emission and absorption spectra.
2. the Rutherford-Geiger-Marsden scattering experiment.
3. observations related to the wave nature of light.
4. the neutron-to-proton ratio of stable elements.

Question 60 

What part of the nuclear power plant conveys energy from the reactors to the turbines?

1. Control rods
2. Moderator
3. Heat exchanger
4. Reactor vessel

Question 61 

Green light is incident on the surface of a metal plate and as a result, photoelectrons are emitted. 

What change might cause the emission of photoelectrons to stop?

1. Decreasing the work function of the metal plate.
2. Decreasing the intensity of the incident light.
3. Changing green light to red light.
4. Changing green light to violet light.

Question 62 

Which of the following properties is affected when a nucleus decays through gamma-decay?

1. The proton number of the nucleus
2. The charge of the nucleus
3. The neutron number of the nucleus
4. The energy state of the nucleus

Question 63 

What is the number of neutrons and the number of protons in the nucleus of a _{11}^{24}\textrm{Na} atom?

Question 64

Which of the following quantities can be directly determined from the emission spectrum of a star?

1. Exact mass
2. Chemical composition
3. Luminosity
4. Apparent brightness

Question 65 

The initial number of nuclides in a pure sample of radioactive isotope is N_{0}. Which graph correctly shows how N, the number of undecayed nuclides in the sample varies with time?

Question 2 

A pulse is travelling on a string that has one end fixed to a wall.

When the pulse reaches the wall, it is reflected. 

a. Sketch the pulse after it has been reflected at the wall.

  [1]

The end of the string is vibrated vertically so that a transverse wave travels through the string. The time period of the vibrations is 1.62 s. The length of the string is 1.95 m.

b. Distinguish between a transverse and a longitudinal travelling wave.

   [2]

c. Calculate the speed of the wave. Give your answer to an appropriate number of significant figures.

   [3]

Question 3 

An expandable balloon is filled with a fixed mass of argon-40 gas. The pressure of the gas is maintained at 1.3 kPa. The graph shows how the volume of the gas varies with temperature.

a. State two assumptions of the kinetic model of an ideal gas.

  [2]

b. Explain why argon-40 behaves as an ideal gas for temperatures between 20 \: ^{\circ}C and 70 \: ^{\circ}C.

  [2]

c. Find the mass of the argon-40 gas in the balloon.

  [2]

Question 4 

Gadolinium-149 \left ( _{\, \, \, 64}^{149}\textrm{Gd} \right ) decays into samarium-145 \left ( _{\, \, \, 62}^{145}\textrm{Sm} \right ) through alpha decay.

The following data is provided:

Binding energy per nucleon for samarium: 8.293 MeV

Binding energy per nucleon for helium: 7.073 MeV

Energy released during the decay: 4.827 \times 10^{-13} J

a. State what is meant by binding energy of a nucleus.

   [1]

b. Calculate the binding energy per nucleon for gadolinium-149. Give your answer in MeV.

  [3]

A pure sample of gadolinium-149 decays into samarium-145. After 46.4 days \frac{number\: of\: gadolinium\: nuclides}{number\: of\: samarium\: nuclides} \approx 0.0323.

c. Estimate the half-life of gadolinium-149.

 [3]