Tagged ERQ exemplars
Real Physics HL Paper 2 ERQs, parsed and structured. 26 ERQs total · showing 20 on page 1 of 2.
Q1 · 16 marks
A.2 Forces and momentum
physics/HL/past_papers/archive_org/2018 May Examination Session/Physics_paper_2__TZ1_HL.pdf
An elastic climbing rope is tested by fixing one end of the rope to the top of a crane. The other end of the rope is connected to a block which is initially at position A. The block is released from rest. The mass of the rope is negligible. diagram not to scale A block 60.0 m rope B C The unextended length of the rope is 60.0 m. From position A to position B, the block…
5 parts
-
(a)
Calculate [2m]
— At position B the rope starts to extend. Calculate the speed of the block at position B. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(b)(i)
Determine [2m · AO3]
— Determine the magnitude of the average resultant force acting on the block between B and C. …
-
(b)(ii)
Sketch [2m · AO3]
— Sketch on the diagram the average resultant force acting on the block between B and C. The arrow on the diagram represents the weight of the block. …
-
(b)(iii)
Calculate [2m · AO2]
— Calculate the magnitude of the average force exerted by the rope on the block between B and C. …
-
(c)(i)
? [1m · ?]
— between A and B. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(ii)
? [1m · ?]
— between B and C. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)
Suggest [2m]
— The length reached by the rope at C is 77.4 m. Suggest how energy considerations could be used to determine the elastic constant of the rope. …
-
(e)(i)
Calculate [2m · AO2]
— Calculate the time taken for the block to return to the equilibrium position for the first time. …
-
(e)(ii)
Calculate [2m · AO2]
— Calculate the speed of the block as it passes the equilibrium position. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
A beam of coherent monochromatic light from a distant galaxy is used in an optics experiment on Earth.
4 parts
-
(a)(i)
Explain [3m · AO3]
— A series of dark and bright fringes appears on the screen. Explain how a dark fringe is formed. …
-
(a)(ii)
Outline [1m · AO2]
— Outline why the beam has to be coherent in order for the fringes to be visible. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(a)(iii)
Calculate [2m · AO2]
— The wavelength of the beam as observed on Earth is 633.0 nm. The separation between a dark and a bright fringe on the screen is 4.50 mm. Calculate D. …
-
(b)(i)
Calculate [3m · AO2]
— Calculate the angular separation between the central peak and the missing peak in the double-slit interference intensity pattern. State your answer to an appropriate number of significant figures. …
-
(b)(ii)
Deduce [2m · AO3]
— Deduce, in mm, the width of one slit. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)
Explain [2m]
— The wavelength of the light in the beam when emitted by the galaxy was 621.4 nm. Explain, without further calculation, what can be deduced about the relative motion of the galaxy and the Earth. …
-
(d)(i)
Calculate [1m · AO2]
— Calculate the wavelength of the light in water. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(ii)
State [2m · AO1]
— State two ways in which the intensity pattern on the screen changes. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
Q7 · 11 marks
physics/HL/past_papers/archive_org/2018 May Examination Session/Physics_paper_2__TZ1_HL.pdf
A capacitor consists of two parallel square plates separated by a vacuum. The plates are 2.5 cm × 2.5 cm squares. The capacitance of the capacitor is 4.3 pF.
5 parts
-
(a)
Calculate [1m]
— Calculate the distance between the plates. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(b)
Calculate [2m]
— The capacitor is connected to a 16 V cell as shown. diagram not to scale capacitor 16 V plate A Calculate the magnitude and the sign of the charge on…
-
(c)
Explain [2m]
— The capacitor is fully charged and the space between the plates is then filled with a dielectric of permittivity ε = 3.0ε0. Explain whether the magnitude of the charge on plate A increases, decreases …
-
(d)
Determine [3m]
— In a different circuit, a transformer is connected to an alternating current (ac) supply. ac supply output voltage primary coil …
-
(e)
Describe [3m]
— Describe the use of transformers in electrical power distribution. [3] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
Hydrogen atoms in an ultraviolet (UV) lamp make transitions from the first excited state to the ground state. Photons are emitted and are incident on a photoelectric surface as shown. UV lamp photons photoelectric surface collecting plate electrons variable voltage source
3 parts
-
(a)
Show [2m]
— Show that the energy of photons from the UV lamp is about 10 eV. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(b)(i)
Calculate [2m · AO2]
— Calculate, in J, the maximum kinetic energy of the emitted electrons. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(b)(ii)
Suggest [2m · AO3]
— Suggest, with reference to conservation of energy, how the variable voltage source can be used to stop all emitted electrons from reaching the collecting plate. [2] . . . . . . . . . . . . . . . . . …
-
(b)(iii)
? [1m · ?]
— The variable voltage can be adjusted so that no electrons reach the collecting plate. Write down the minimum value of the voltage for which no electrons reach the collecting plate. …
-
(c)(i)
? [2m · ?]
— On the diagram, draw and label the equipotential lines at -0.4 V and -0.8 V. [2]
-
(c)(ii)
Calculate [2m · AO2]
— An electron is emitted from the photoelectric surface with kinetic energy 2.1 eV. Calculate the speed of the electron at the collecting plate. …
(a) A small ball of mass m is moving in a horizontal circle on the inside surface of a frictionless hemispherical bowl. bowl N ball The normal reaction force N makes an angle to the horizontal. (i) State the direction of the resultant force on the ball. [1] . . . . . . . . . . . . . . . . . . . . . . . . . .…
4 parts
-
(b)
Determine [4m]
— The radius of the bowl is 8.0 m and = 22˚. Determine the speed of the ball. [4] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(c)
Outline [2m]
— Outline whether this ball can move on a horizontal circular path of radius equal to the radius of the bowl. …
-
(d)(i)
Outline [1m · AO2]
— Outline why the ball will perform simple harmonic oscillations about the equilibrium position. …
-
(d)(ii)
Show [2m · AO3]
— Show that the period of oscillation of the ball is about 6 s. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(iii)
? [3m · ?]
— The amplitude of oscillation is 0.12 m. On the axes, draw a graph to show the variation with time t of the velocity v of the ball during one period. [3] v / m s–1 0.2 0.1 0.0 2 …
-
(e)
Calculate [3m]
— A second identical ball is placed at the bottom of the bowl and the first ball is displaced so that its height from the horizontal is equal to 8.0 m. first ball 8.0 m second ball The first ball is rel…
Q8 · 10 marks
B.5 Current and circuits
physics/HL/past_papers/archive_org/2018 May Examination Session/Physics_paper_2__TZ2_HL.pdf
A negatively charged thundercloud above the Earth’s surface may be modelled by a parallel plate capacitor. thundercloud thundercloud base air 1600 m Earth’s surface The lower plate of the capacitor is the Earth’s surface and the upper plate is the base of the thundercloud. The following data are available. Area of thundercloud base = 1.2 × 108 m2 Charge on thundercloud ba…
4 parts
-
(a)
Show [1m]
— Show that the capacitance of this arrangement is C = 6.6 × 10–7 F. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(b)(i)
? [2m · ?]
— in V, the potential difference between the thundercloud and the Earth’s surface. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(b)(ii)
? [2m · ?]
— in J, the energy stored in the system. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(i)
Show [3m · AO3]
— Show that about –11 C of charge is delivered to the Earth’s surface. [3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(ii)
Calculate [1m · AO2]
— Calculate, in A, the average current during the discharge. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)
State [1m]
— State one assumption that needs to be made so that the Earth-thundercloud system may be modelled by a parallel plate capacitor. …
(a) Rutherford constructed a model of the atom based on the results of the alpha particle scattering experiment. Describe this model. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
4 parts
-
(b)
Outline [3m]
— Bohr modified the Rutherford model by introducing the condition mvr = n . Outline the reason for this modification. 2π …
-
(c)(ii)
? [2m · ?]
— Using the answer in (b) and (c)(i), deduce that the radius r of the electron’s orbit in the ground state of hydrogen is given by the following expression. …
-
(c)(iii)
Calculate [1m · AO2]
— Calculate the electron’s orbital radius in (c)(ii). [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(i)
Explain [3m · AO3]
— Explain what may be deduced about the energy of the electron in the b – decay. [3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(ii)
Suggest [1m · AO3]
— Suggest why the b – decay is followed by the emission of a gamma ray photon. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(iii)
Calculate [2m · AO2]
— Calculate the wavelength of the gamma ray photon in (d)(ii). [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(e)(i)
Draw [1m · AO1]
— Draw a labelled arrow to complete the Feynman diagram. [1]
-
(e)(ii)
Identify [1m · AO2]
— Identify particle V. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
Q1 · 10 marks
physics/HL/past_papers/archive_org/2018 November Examination Session/Physics_paper_2__HL.pdf
Ion-thrust engines can power spacecraft. In this type of engine, ions are created in a chamber and expelled from the spacecraft. The spacecraft is in outer space when the propulsion system is turned on. The spacecraft starts from rest. ions spacecraft direction of direction of ion movement spacecraft motion The mass of ions e…
3 parts
-
(a)
Determine [2m]
— Determine the initial acceleration of the spacecraft. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . …
-
(b)(i)
Estimate [2m · AO2]
— Estimate the maximum speed of the spacecraft. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(b)(ii)
Outline [1m · AO2]
— Outline why the answer to (b)(i) is an estimate. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(b)(iii)
Outline [1m · AO2]
— Outline why scientists sometimes use estimates in making calculations. [1] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(i)
Outline [2m · AO2]
— Outline why the ions are likely to spread out. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(ii)
Explain [2m · AO3]
— Explain what effect, if any, this spreading of the ions has on the acceleration of the spacecraft. …
A lighting system consists of two long metal rods with a potential difference maintained between them. Identical lamps can be connected between the rods as required. power supply rod 24 V, 5.0 W rod The following data are available for the lamps when at their working temperature. Lamp specifications 24 V, 5.0 W Power supply root me…
4 parts
-
(a)
Calculate [3m]
— Each rod is to have a resistance no greater than 0.10 Ω. Calculate, in m, the minimum radius of each rod. Give your answer to an appropriate number of significant figures. …
-
(b)
Calculate [2m]
— Calculate the maximum number of lamps that can be connected between the rods. Neglect the resistance of the rods. …
-
(c)
Outline [1m]
— One advantage of this system is that if one lamp fails then the other lamps in the circuit remain lit. Outline one other electrical advantage of this system compared to one in which the lamps are conn…
-
(d)(i)
Outline [2m · AO2]
— Outline how eddy currents reduce transformer efficiency. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(d)(ii)
Determine [4m · AO3]
— Determine the peak current in the primary coil when operating with the maximum number of lamps. …
There is a proposal to place a satellite in orbit around planet Mars.
3 parts
-
(a)(ii)
Suggest [2m · AO3]
— Newton’s law of gravitation applies to point masses. Suggest why the law can be applied to a satellite orbiting Mars. …
-
(b)(i)
Show [3m · AO3]
— Mars has a mass of 6.4 × 10 23 kg. Show that, for Mars, k is about 9 × 10–13 s2 m–3. [3] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(b)(ii)
Calculate [2m · AO2]
— The time taken for Mars to revolve on its axis is 8.9 × 104 s. Calculate, in m s–1, the orbital speed of the satellite. …
-
(c)(i)
Show [2m · AO3]
— Show that the intensity of solar radiation at the orbit of Mars is about 600 W m–2. [2] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…
-
(c)(ii)
Determine [2m · AO3]
— Determine, in K, the mean surface temperature of Mars. Assume that Mars acts as a black body. …
-
(c)(iii)
Outline [3m · AO2]
— The atmosphere of Mars is composed mainly of carbon dioxide and has a pressure less than 1 % of that on Earth. Outline why the mean temperature of Earth is strongly affected by gases in its atmosphere…
A girl rides a bicycle that is powered by an electric motor. A battery transfers energy to the electric motor. The emf of the battery is 16 V and it can deliver a charge of 43 kC when discharging completely from a full charge.
5 parts
-
(a)(i)
Show [1m · AO3]
— Show that the time taken for the battery to discharge is about 3 × 103 s. [1] ��������������������������������������������������������������…
-
(a)(ii)
Deduce [2m · AO3]
— Deduce that the average power output of the battery is about 240 W. [2] ��������������������������������������������������������������…
-
(a)(iii)
Determine [2m · AO3]
— Friction and air resistance act on the bicycle and the girl when they move. Assume that all the energy is transferred from the battery to the electric motor. Determine the total average resistive forc…
-
(b)(i)
Calculate [1m · AO2]
— Calculate the component of weight for the bicycle and girl acting down the slope. [1] ��������������������������������������������������������������…
-
(b)(ii)
Calculate [2m · AO2]
— The battery continues to give an output power of 240 W. Assume that the resistive forces are the same as in (a)(iii). Calculate the maximum speed of the bicycle and the girl up the slope. …
-
(c)
Explain [2m]
— On another journey up the slope, the girl carries an additional mass. Explain whether carrying this mass will change the maximum distance that the bicycle can travel along the slope. …
-
(d)
Determine [2m]
— The bicycle has a meter that displays the current and the terminal potential difference (pd) for the battery when the motor is running. The diagram shows the meter readings at one instant. The emf of …
-
(e)(i)
? [1m · ?]
— the emf of one cell. [1] ��������������������������������������������������������������…
-
(e)(ii)
? [2m · ?]
— the internal resistance of one cell. [2] ��������������������������������������������������������������…
A small metal pendulum bob is suspended at rest from a fixed point with a length of thread of negligible mass. Air resistance is negligible. The pendulum begins to oscillate. Assume that the motion of the system is simple harmonic, and in one vertical plane. The graph shows the variation of kinetic energy of the pendulum bob with time. 20 15 kinetic energy / mJ 10 5 0 0 0.25 0.5 0.75 1.0…
2 parts
-
(a)(ii)
? [1m · ?]
— Label on the graph with the letter X a point where the speed of the pendulum is half that of its initial speed. …
-
(a)(iii)
Show [2m · AO3]
— The mass of the pendulum bob is 75 g. Show that the maximum speed of the bob is about 0.7 m s–1.[2] ��������������������������������������������������������������������������������������������������…
-
(b)(i)
Calculate [1m · AO2]
— Calculate the speed of the combined masses immediately after the collision. [1] ��������������������������������������������������������������…
-
(b)(ii)
Show [3m · AO3]
— Show that the collision is inelastic. [3] ��������������������������������������������������������������…
-
(b)(iii)
Sketch [2m · AO3]
— Sketch, on the axes, a graph to show the variation of gravitational potential energy with time for the bob and the object after the collision. The data from the graph used in (a) is shown as a dashed …
-
(b)(iv)
Explain [3m · AO3]
— The speed after the collision of the bob and the object was measured using a sensor. This sensor emits a sound of frequency f and this sound is reflected from the moving bob. The sound is then detecte…
A student strikes a tennis ball that is initially at rest so that it leaves the racquet at a speed of 64 m s–1. The ball has a mass of 0.058 kg and the contact between the ball and the racquet lasts for 25 ms.
3 parts
-
(a)(i)
? [2m · ?]
— average force exerted by the racquet on the ball. [2] ����������������������������������������������������������������…
-
(a)(ii)
? [2m · ?]
— average power delivered to the ball during the impact. [2] ����������������������������������������������������������������…
-
(b)(i)
Calculate [2m · AO2]
— Calculate the time it takes the tennis ball to reach the net. [2] ��������������������������������������������������������������…
-
(b)(ii)
Show [3m · AO3]
— Show that the tennis ball passes over the net. [3] ��������������������������������������������������������������…
-
(b)(iii)
Determine [2m · AO3]
— Determine the speed of the tennis ball as it strikes the ground. [2] ��������������������������������������������������������������…
-
(c)
Predict [3m]
— The student models the bounce of the tennis ball to predict the angle θ at which the ball leaves a surface of clay and a surface of grass. θ surface sliding The model assumes • during contact with t…
Q3 · 10 marks
C.2 Wave model
physics/HL/past_papers/archive_org/2019 May Examination Session/Physics_paper_2__TZ2_HL.pdf
The diagram shows the direction of a sound wave travelling in a metal sheet. diagram not to scale metal sheet normal P wave 54° direction air Q
5 parts
-
(a)
Calculate [2m]
— Particle P in the metal sheet performs simple harmonic oscillations. When the displacement of P is 3.2 µm the magnitude of its acceleration is 7.9 m s-2. Calculate the magnitude of the acceleration of…
-
(b)
Calculate [2m]
— The wave is incident at point Q on the metal–air boundary. The wave makes an angle of 54° with the normal at Q. The speed of sound in the metal is 6010 m s–1 and the speed of sound in air is 340 m s–1…
-
(c)
Determine [1m]
— The frequency of the sound wave in the metal is 250 Hz. Determine the wavelength of the wave in air. …
-
(d)(i)
? [1m · ?]
— draw an arrow to indicate the acceleration of this molecule. [1]
-
(d)(ii)
? [1m · ?]
— label with the letter C a point in the pipe that is at the centre of a compression. [1]
-
(e)(i)
? [2m · ?]
— frequency heard by the observer. [2] ��������������������������������������������������������������…
-
(e)(ii)
? [1m · ?]
— wavelength measured by the observer. [1] ��������������������������������������������������������������…
Three identical light bulbs, X, Y and Z, each of resistance 4.0 Ω are connected to a cell of emf 12 V. The cell has negligible internal resistance. 12 V S X Y Z
4 parts
-
(a)
Calculate [2m]
— The switch S is initially open. Calculate the total power dissipated in the circuit. [2] �����������������������������������������������������…
-
(b)(i)
State [1m · AO1]
— State, without calculation, why the current in the cell will increase. [1] ��������������������������������������������������������������…
-
(b)(ii)
Deduce [2m · AO3]
— Deduce the ratio .[2] power dissipated in Y with S closed ���������������������������������������������������������������������������������������������…
-
(c)
Calculate [1m]
— The cell is used to charge a parallel-plate capacitor in a vacuum. The fully charged capacitor is then connected to an ideal voltmeter. V The capacitance of the capacitor is 6.0 µF and the reading of …
-
(d)(i)
Calculate [3m · AO2]
— Calculate the change in the energy stored in the capacitor. [3] ��������������������������������������������������������������…
-
(d)(ii)
Suggest [1m · AO3]
— Suggest, in terms of conservation of energy, the cause for the above change.[1] ����������������������������������������������������������������������������������������������������������������������…
The lens of an optical system is coated with a thin film of magnesium fluoride of thickness d. Monochromatic light of wavelength 656 nm in air is incident on the lens. The angle of incidence is θ . Two reflected rays, X and Y, are shown. X Y θ magnesium fluoride d lens The following refractive indices are available. Air …
3 parts
-
(a)
Predict [2m]
— Predict whether reflected ray X undergoes a phase change. [2] �����������������������������������������������������…
-
(b)(i)
? [1m · ?]
— state, in terms of d , the path difference between the reflected rays X and Y. [1] ��������������������������������������������������������������…
-
(b)(ii)
? [2m · ?]
— calculate the smallest value of d that will result in destructive interference between ray X and ray Y. …
-
(b)(iii)
? [2m · ?]
— discuss a practical advantage of this arrangement. [2] ��������������������������������������������������������������…
-
(c)(i)
Draw [2m · AO1]
— Draw, on the axes, the variation with diffraction angle of the intensity of light incident on the retina of the observer. …
-
(c)(ii)
Estimate [2m · AO2]
— Estimate, in rad, the smallest angular separation of two distinct point sources of light of wavelength 656 nm that can be resolved by the eye of this observer. …
Q4 · 12 marks
C.2 Wave model
physics/HL/past_papers/archive_org/2020 November Examination Session/Physics_paper_2__HL.pdf
Two loudspeakers, A and B, are driven in phase and with the same amplitude at a frequency of 850 Hz. Point P is located 22.5 m from A and 24.3 m from B. The speed of sound is 340 m s–1. P 22.5 m A 24.3 m B
4 parts
-
(a)
Deduce [4m]
— Deduce that a minimum intensity of sound is heard at P. [4] �����������������������������������������������������…
-
(b)
Predict [2m]
— A microphone moves along the line from P to Q. PQ is normal to the line midway between the loudspeakers. P direction of travel A Q B The intensity of sound is detected by the microphone. Predict the v…
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(c)
Estimate [2m]
— When both loudspeakers are operating, the intensity of sound recorded at Q is I0. Loudspeaker B is now disconnected. Loudspeaker A continues to emit sound with unchanged amplitude and frequency. The i…
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(d)(i)
Explain [2m · AO3]
— Explain why the frequency recorded by the microphone is lower than the frequency emitted by the loudspeaker. …
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(d)(ii)
Calculate [2m · AO2]
— Calculate v.[2] ��������������������������������������������������������������������������������������������������������������������������������������������������� ���������������������������������…
Two players are playing table tennis. Player A hits the ball at a height of 0.24 m above the edge of the table, measured from the top of the table to the bottom of the ball. The initial speed of the ball is 12.0 m s-1 horizontally. Assume that air resistance is negligible. 12.0 m s−1 diagram not to scale 0.24 m net table
4 parts
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(a)
Show [1m]
— Show that the time taken for the ball to reach the surface of the table is about 0.2 s. [1] �����������������������������������������������������…
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(b)
Sketch [2m]
— Sketch, on the axes, a graph showing the variation with time of the vertical component of velocity vv of the ball until it reaches the table surface. Take g to be +10 m s-2.[2] 3 2 vV / m s −1 1 0 …
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(c)
Show [3m]
— The net is stretched across the middle of the table. The table has a length of 2.74 m and the net has a height of 15.0 cm. Show that the ball will go over the net. …
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(d)(i)
Determine [2m · AO3]
— Determine the kinetic energy of the ball immediately after the bounce. [2] ��������������������������������������������������������������…
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(d)(ii)
Calculate [3m · AO2]
— Player B intercepts the ball when it is at its peak height. Player B holds a paddle (racket) stationary and vertical. The ball is in contact with the paddle for 0.010 s. Assume the collision is elasti…
A mass of 1.0 kg of water is brought to its boiling point of 100 °C using an electric heater of power 1.6 kW.
4 parts
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(a)(ii)
State [1m · AO1]
— State one assumption of the kinetic model of an ideal gas. [1] ��������������������������������������������������������������…
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(b)(i)
Estimate [2m · AO2]
— Estimate the specific latent heat of vaporization of water. State an appropriate unit for your answer. …
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(b)(ii)
Explain [1m · AO3]
— Explain why the temperature of water remains at 100 °C during this time. [1] ��������������������������������������������������������������…
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(c)
Determine [3m]
— The heater is removed and a mass of 0.30 kg of pasta at -10 °C is added to the boiling water. Determine the equilibrium temperature of the pasta and water after the pasta is added. Other heat transfer…
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(d)(i)
Show [1m · AO3]
— Show that each resistor has a resistance of about 30 Ω. [1] ��������������������������������������������������������������…
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(d)(ii)
Calculate [2m · AO2]
— Calculate the power transferred by the heater when both switches are closed. [2] ��������������������������������������������������������������…
A device sends an impulse of electrical energy to maintain a regular heartbeat in a person. The device is powered by an alternating current (ac) supply connected to a step-up transformer that charges a capacitor of capacitance 30 μF. A B switch 220 V heart
4 parts
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(a)
Explain [2m]
— Explain the role of the diode in the circuit when the switch is at position A. [2] �����������������������������������������������������…
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(b)(i)
Show [2m · AO3]
— Show that the maximum energy stored by the capacitor is about 160 J. [2] ��������������������������������������������������������������…
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(b)(ii)
Calculate [1m · AO2]
— Calculate the maximum charge Q0 stored in the capacitor. [1] ��������������������������������������������������������������…
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(b)(iii)
Identify [1m · AO2]
— Identify, using the label + on the diagram, the polarity of the capacitor. [1]
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(c)(i)
Describe [1m · AO2]
— Describe what happens to the energy stored in the capacitor when the switch is moved to position B. …
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(c)(ii)
Show [1m · AO3]
— Show that the charge remaining in the capacitor after a time equal to one time constant τ of the circuit will be 0.37 Q0.[1] �������������������������������������������������������������������������…
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(c)(iii)
Determine [2m · AO3]
— The graph shows the variation with time of the charge in the capacitor as it is being discharged through the heart. 1.0 Q/Q0 0 0 1 2 3 …
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(d)
Explain [2m]
— In practice, two electrodes connect the heart to the circuit. These electrodes introduce an additional capacitance. B electrode heart capacitance Explain the effect of the electrode capacitance on the…