Student Number
2014
TRIAL HIGHER SCHOOL
CERTIFICATE
EXAMINATION
Physics
Total marks – 100
Section I
General Instructions

Reading time – 5 minutes

Working time – 3 hours

Write using black or blue pen

Draw diagrams using pencil

Approved calculators may be
used
A data sheet, formulae sheets
and Periodic Table are provided
at the back of this paper
Write your student number in the
space provided


75 marks
This section has two parts, Part A and Part B
Part A – 20 marks
 Attempt Questions 1-20
 Allow about 35 minutes for this part
Part B – 55 marks
 Attempt Questions 21-32
 Allow about 1 hour and 40 minutes for this part
Section II
25 marks
 Attempt ONE Question from Questions 33-37
 Allow about 45 minutes for this section
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the High School Certificate Examination in accordance with the Board of Studies requirements. No guarantee or warranty is made or
implied that this examination paper mirrors in every respect the actual HSC Examination paper for this course.
Section I
75 marks
Part A – 20 marks
Attempt Questions 1-20
Allow about 35 minutes for this part
Use the multiple-choice answer sheet for questions 1-20.
1.
A 3200 kg satellite is placed into a circular orbit at an altitude of 2.4 x 105 m above the
Earth’s surface. The period of this satellite is closest to: (Radius of the Earth = 6370 km)
(A) 4700 s
(B) 4900 s
(C) 5100 s
(D) 5300 s
2.
A magnet is moving towards an aluminium ring.
In which way will the current flow in the labelled portion of the ring as the magnet
moves towards the ring?
(A)
towards 1
(B)
towards 2
(C)
towards 3
(D)
towards 4
-2-
3.
An AC induction motor has:
(A) a rotor
(B) carbon brushes
(C) a slip ring commutator
(D) a split ring commutator
4.
A rocket passes a space station at a speed 0.90 c parallel to the side of the space station.
There is a circular window on the space station, as shown below.
direction of rocket
window of space station
A person inside the passing rocket observes the window. Which of the following figures
best shows how the window would look to the person on the passing rocket?
(A)
(B)
(C)
5.
(D)
Muons and antimuons are anti-particles of each other. They both have the same mass.
When a muon meets an antimuon, both are destroyed and two photons are formed. If the
two particles are stationary, then the two photons that form have a combined energy of
3.38 × 10-11 J. Using this data, which of the following is closest to the mass of a single
muon?
(A)
1.60 × 10-19 kg
(B)
5.64 × 10-20 kg
(C)
1.88 × 10-28 kg
(D)
3.76 × 10-28 kg
-3-
6.
A coil moves at a constant velocity across a region of magnetic field as shown.
1
magnetic field into page
2
Which of the following correctly shows the graph of emf against time for the emf
induced in the coil as it moves from 1 to 2?
7.
A ball rolls off of the end of a table at 2.5 m s-1. The table top is 1.5 m above the floor.
How much time passes before the ball hits the floor?
(A) 0.55 s
(B) 0.60 s
(C) 1.20 s
(D) 1.35 s
-4-
8.
Bill and Ben both stand on the edge of a cliff. Bill throws a stone vertically downwards
and, at the same time, Ben throws a stone vertically upwards. The speed v at which both
stones are thrown is the same. Neglecting air resistance, which of the following
statements is true?
v (Ben)
v (Bill)
sea
(A) The stone thrown by Bill will hit the sea with greater speed than the stone thrown by
Ben.
(B) Both stones will hit the sea with the same speed no matter what the height of the
cliff.
(C) In order to determine which stone hits the sea first the height of the cliff must be
known.
(D) In order to determine which stone hits the sea first both the height of the cliff and the
mass of each stone must be known
9.
Which of the following situations induces the greatest current flow in the coil? (All
magnets and coils are identical.)
-5-
10. When violet light hitting hits the negative electrode in a vacuum tube, a current flows in
the tube. Under the same conditions, which form of light will always cause a current to
flow?
(A) Blue
(B) Green
(C) Infrared
(D) Ultraviolet
11. The mass of the planet Uranus is 14.5 times greater than that of the Earth and its radius is
4.0 times that of the Earth. Which of the following is the best approximation of the
acceleration due to gravity on the surface of Uranus?
(A) 8.9 m s-2
(B) 12 m s-2
(C) 44 m s-2
(D) 170 m s-2
12. A boy is standing exactly midway between two posts, X and Y. At the instant a car
passes him, the driver sends simultaneous flashes of light forwards and backwards
towards the posts. The car is travelling at 0.95c towards post Y, as shown in the diagram
below.
Post Y
Post X
0.95c
Which of the following best describes when the flashes of light reach the posts, as
observed by the boy?
(A)
Post X receives the flash of light first.
(B)
Post Y receives the flash of light first.
(C)
Post X and Post Y receive a flash of light at the same time.
(D)
It is not possible predict which post receives a flash of light first.
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13. A blue laser and a red laser both have the same power output and shine onto a metal
surface. Which of the following is correct?
(A) The blue laser produces more photons every second than the red laser.
(B) The red laser produces more photons every second than the blue laser.
(C) The red laser and the blue laser produce the same number of photons per second.
(D) The number of photons produced per second depends on the threshold frequency of
the metal.
14. Classical physics was unable to explain which of the following:
(A)
A black body does not reflect any radiation, it only emits radiation.
(B)
At temperatures over 1500 K the radiation emitted by a black body is in the infrared region.
(C)
The work function of a metal depends on the type of material is it made from.
(D)
The lack of increase in radiation in the ultra-violet region at high temperatures.
15. In a step-down transformer, which of the following is greater in the secondary coil than
in the primary coil?
(A)
power
(B)
current
(C)
voltage
(D)
number of turns
16. A current of flows through a solenoid as shown in the diagram below. The direction of
the magnetic field inside the solenoid is:
(A) to the left
(B) to the right
(C) up
(D) down
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17. Which of the following changes is most likely to decrease the resistance of a particular
wire?
(A)
increasing the diameter of the wire
(B)
increasing the length of the wire
(C)
increasing the temperature of the wire
(D)
adding impurities to the metal that makes up the wire
18. Which of the following best describes the material in a p-type semiconductor?
(A)
Extremely pure germanium with some of the electrons removed leaving holes in
the resulting crystal lattice.
(B)
Extremely pure germanium with extra electrons added leaving some free electrons
in the resulting crystal lattice.
(C)
Pure germanium that has small amounts of a element, that has one less valence
electron than a germanium atom, added to result in a crystal lattice where some of
the germanium atoms in the lattice have a space for another electron.
(D)
Pure germanium that has small amounts of a element, that has one more valence
electron than a germanium atom, added to result in a crystal lattice with extra
electrons.
19. Hertz used a high voltage source to produce a spark and realised that when another spark
was observed at a receiving coil, energy must have been transferred.
Receiving coil
high voltage spark
Hertz noticed that it was possible to increase the strength of the spark in the receiving
coil. Which of the following best describes what Hertz did to produce a stronger spark?
(A) He placed a sheet of glass in front of the receiving coil.
(B) He slightly increased the gap between the terminals of the receiving coil.
(C) He shone a source of ultraviolet light on the receiving coil.
(D) He placed a flat sheet of metal behind the high voltage spark to reflect energy to the
receiving coil.
-8-
20. In 1900, Planck suggested a mathematical formula that predicted an intensity-wavelength
relationship for a black body that agreed with the experimental results. The success of
this formula depended on which of the following hypotheses?
(A) The intensity of light is dependent on the wavelength.
(B) Light is quantised, with the energy of the light quanta depending on the frequency.
(C) Light is a wave whose intensity can be found using a mathematical formula.
(D) Light is quantised, with the energy of the light quanta depending on the size of the
cavity from which it is emitted.
Part B follows on the next page
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Part B – 55 marks
Student Number
Attempt Questions 21-31
Allow about 1 hour and 40 minutes for this part.
Answer the questions in the spaces provided.
Show all relevant working in questions involving calculations.
Question 21 (3 marks)
The diagram below shows a cross-section of a microphone. Describe how the speech of a
person talking near the diaphragm of the microphone can be converted into an electrical
signal that is received by an amplifier.
3
Diagram from www.scsa.wa.edu.au/internet/_Documents/PHY_public/Physics_Stage_3_examination_2011.pdf
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Question 22 (5 marks)
The graph below shows the variation of gravitational potential energy (EP) of a 1 kg mass
with distance R from the centre of the Earth.
0
-1
-2
Ep (x 107 J)
-3
-4
-5
-6
-7
-8
0
5
10
15
20
25
30
35
40
45
50
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R (x 10 m)
(a) Use the graph to find the gravitational potential energy at:
(i) the surface of the Earth - take the radius of the Earth as 6.4 x 106 m.
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(ii) at a height of 2.5 x 107 m above the surface of the Earth.
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(b) Use the values you have found in part (a) to calculate the minimum energy required to
put a satellite of mass 2.0 x 104 kg into an orbit of a height of 2.5 x 107 m above the
surface of the Earth.
1
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Question 22 continues on the following page
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Question 22 continued
(c)
Give two reasons why in practice more energy is required to put this satellite in orbit
than what you calculated in part (b).
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Question 23 (4 marks)
Metals, n-type semiconductors and p-type semiconductors all conduct electricity.
(a)
Identify the relative number of free electrons in each of these three materials.
1
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(b)
Describe how each of these materials conducts electricity.
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Question 24 (6 marks)
(a) The term escape velocity is often defined as the minimum initial velocity an object must
have at the surface of a planet in order to escape the gravitational attraction of the planet.
Explain what is meant by the phrase “to escape the gravitational attraction of the
planet.”
1
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(b) An asteroid has a radius of 40 km and a mass of 3.5 x 1016 kg. Estimate the minimum
velocity which an astronaut of mass 80 kg would have to jump off the surface of the
asteroid if they were to escape the gravitational attraction of the asteroid.
2
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A
(c ) (i) The diagram opposite represents the asteroid in part (b).
An astronaut runs up the top of a small hill, at A, and jumps off horizontally. Calculate
the velocity with which he would have to launch himself in order to go into a low,
circular orbit.
2
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(ii) On the diagram above sketch the path an astronaut might follow if he launched
himself at about ¼ of the speed required for circular orbit.
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1
Question 25 (6 marks)
Astronauts travel to Alpha Centauri, 4.2 light years away, at a constant speed of 0.84 c.
(a)
How many years will it take for them to get there as measured by:
(i) observers in the Earth’s frame of reference?
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(ii) the astronauts?
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(b)
On arrival at Alpha Centauri the astronauts immediately return to Earth at the same
speed. On their arrival back on Earth, how much time has passed since the astronauts
first left Earth, as measured by:
(i) observers on the Earth?
1
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(ii) the astronauts?
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(c)
The astronauts find that, after the return journey, a different amount of time has passed
according to their clocks compared to the clocks of someone who remained on Earth.
(i) This is often referred as a paradox. Explain why the term paradox is used.
1
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(ii) Explain how this paradox is resolved.
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Question 26 (5 marks)
The photograph below shows a typical transformer such as that used to change 240 V AC to
12 V AC.
Diagram from www.scsa.wa.edu.au/internet/_Documents/PHY_public/Physics_Stage_3_examination_2011.pdf
(a)
(b)
Label the photograph above showing clearly the positions of both the primary and
secondary coils.
1
Explain why you labelled the diagram the way you did.
1
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(c)
Discuss the function and design of the transformer core.
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3
Question 27 (5 marks)
The diagram below shows a moving coil meter.
(a)
When a current flows in the rectangular coil, a force is produced on the coil. Explain
the reason for this force.
2
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(b)
The coil has a length of 0.24 m and a width of 0.08 m and has 60 turns. There is a
current of 4.0 A in the coil and it is in a uniform magnetic field of 0.015 T.
(i) Calculate the force on one of the long sides of the coil.
1
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(ii) Hence determine the torque acting on the coil.
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(c)
The spring provides a torque that opposes the coil’s rotation. When there is a current
flowing through the coil, but the coil is not moving describe the relationship between
the torque acting on the coil because of the magnetic field and the torque provided by
the spring.
1
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Question 28 (4 marks)
A simplified sketch of a generator is shown below.
(a) Is the output voltage AC or DC? Give a reason for your answer.
1
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(b) State TWO effects on the output voltage if the coil is made to turn faster.
2
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(c) What is the position of the coil relative to the magnetic field when the output voltage
is a maximum?
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Question 29 (6 marks)
Light is incident on a clean metal surface in a vacuum. The maximum kinetic energy (KEmax)
of the electrons ejected from the surface is measured for different values of the frequency (f)
of the incident light. These measurements are plotted on the graph below.
2.0
1.5
KEmax (x 10-19 J)
1.0
0.5
0.0
4.0
(a)
6.0
6.5
f (x 1014 Hz)
Draw the line of best fit for the plotted data points.
(b)
Use the graph to determine:
(i)
4.5
5.0
5.5
7.0
7.5
8.0
Plank’s constant
1
2
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(ii)
the minimum energy required to eject an electron from the surface of the metal
(the work function)
1
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(c)
Explain how Einstein’s photoelectric theory accounts for the fact that no electrons are
emitted from the surface of a metal if the frequency of the incident light is less than a
certain value.
2
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Question 30 (5 marks)
Discuss how limitations in available communication technology led to the invention of the
transistor.
5
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Question 31 (2 marks)
Outline one advantage and one disadvantage of AC generators when compared to DC
generators.
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2
Question 32 (4 marks)
The graph below shows resistance versus temperature for a superconductor.
resistance (Ω)
0
temperature (K)
Explain the shape of this graph referring to the superconductor’s lattice structure and the
conduction electrons.
4
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Section II
25 marks
Attempt ONE question from Questions 33-37
Allow about 45 minutes for this section
Answer the question in the writing booklets.
Show all relevant working in questions involving calculations.
For Questions 33–36

answer parts (a) - (c) of the question in Section II Answer Booklet 1.

answer parts (d) onwards of the question in Section II Answer Booklet 2.
Extra writing booklets are available.
For Question 37

answer parts (a) - (d) of the question in Section II Answer Booklet 1.

answer parts (e) onwards of the question in Section II Answer Booklet 2.
Extra writing booklets are available.
Show all relevant working in questions involving calculations.
Page
Question 33
Geophysics………………………………… 23
Question 34
Medical Physics…………………………… 24
Question 35
Astrophysics……………………………….. 25
Question 36
From Quanta to Quarks……………………. 27
Question 37
The Age of Silicon………………………… 28
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BLANK PAGE
- 22 -
Question 33 Geophysics (25 marks)
Answer parts (a) - (c) in Section II Answer Booklet 1.
(a) Discuss the difference between seismic p-waves and s-waves in terms of wave type and
wave propagation.
4
(b) Describe the role that geophysics has played in monitoring nuclear test band treaties and
natural hazard reduction.
6
(c) A satellite orbiting the Earth has a period of 7.1 hours.
(i) Calculate the radius of this satellites orbit.
1
(ii) How can this satellite measure changes in the density of the Earth’s crust below it.
3
Answer parts (d) - (e) in Section II Answer Booklet 2.
(d) In the 21st century the concept that the continents have moved relative to each other is
widely accepted. Why did this concept initially prove to be difficult to accept and what
evidence led to this now being accepted?
6
(e) During your study of Geophysics you performed an investigation to demonstrate how the
inclination of the Earth’s magnetic field varies with latitude. Describe clearly, with the
aid of diagrams, your investigation.
5
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Question 34 Medical Physics (25 marks)
Answer parts (a) - (c) in Section II Answer Booklet 1.
(a)
In a PET scan, positrons emitted from the radioisotope combine with electrons in the
body and release two gamma rays. Outline how the position where the two gamma rays
are emitted is determined in a PET scan.
3
(b)
Radioisotopes have been found to be very useful in some medical diagnostic
techniques. Name a radioisotope that is used in diagnostic imaging. In your answer
outline the properties of the radioisotope that make it suitable for this use and describe
how the images created can be used to assist in diagnosing some diseases.
4
(c)
During your study of Medical Physics you performed a first-hand investigation to
demonstrate the transfer of light by optical fibres. Describe, with the aid of diagrams,
your investigation.
5
Answer parts (d) - (g) in Section II Answer Booklet 2.
(d)
A patient has an X-ray image taken of the bones in their leg. Explain how X ray
imaging works.
3
(e)
Describe how the Doppler effect in sound is used to obtain blood flow characteristics in
the heart.
3
(f)
The following table show the speed of sound in various materials and the density of
these materials.
Material
muscle
bone
fat
soft tissue
air
blood
Average velocity of sound (m s-1)
Density of material (kg m-3)
1585
4080
1450
1520
333
1570
1070
1910
952
1040
1.3
1060
(i) Calculate the acoustic impedance of bone and muscle.
2
(ii) The acoustic impedance calculated from part f (i) above can be used to compare the
intensity of the ultrasound beam striking the boundary between a muscle and bone
with the intensity of the beam that is reflected. Calculate the percentage of the
beam that would be reflected at this boundary.
2
(g)
Describe how the composition of the nuclei and the strength of an applied external
magnetic field determine the frequency of precessing of the nuclei.
3
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Question 35 Astrophysics (25 marks)
Answer parts (a) - (c) in Section II Answer Booklet 1.
(a)
Discuss the advantages and disadvantages of placing telescopes in space.
5
(b)
The solar parallax angle θ, as shown in the diagram below, was measured at different
locations on the Earth during the transit of Venus. From these measurements the
distance from the Earth to the Sun was calculated.
Sun
Earth
angle θ
Take the radius of the Earth as 6370 km.
Calculate the Earth – Sun distance in kilometres if the solar parallax angle was
measured as θ = 0.00250°.
(c)
2
Binary stars are named depending on their method of detection and include visual,
astrometric, eclipsing and spectroscopic. Discuss how each of these binaries is
detected and the limitations of the methods used to detect the different types of binary
stars.
6
Answer parts (d) - (f) in Section II Answer Booklet 2.
(d)
A bright star has an apparent magnitude of + 0.5 and an absolute magnitude of - 1.0.
Calculate the distance to this star.
2
(e)
(i) Sketch a labelled Hertzsprung-Russell (H-R) diagram for stars in a globular
cluster.
1
(ii) Sketch a labelled H-R diagram for stars in a young open cluster.
1
(iii) Identify the differences between the diagrams you sketched in parts (e) (i) and (ii)
and explain the reasons for these differences.
2
Question 35 continues on the following page
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(f)
This question refers to the four stars, V, X, Y, and Z shown in the HR diagram below:
(i)
Which of the four stars would have the largest radius? Justify your answer.
(ii)
2
Copy and complete the table below into your answer booklet comparing
stars V and Z in terms of their physical properties, nucleosynthesis and
eventual fate.
4
Feature
Physical
property
Star V
Nucleosynthesis
reaction
Eventual fate
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Star Z
Question 36 From Quanta to Quarks (25 marks)
Answer parts (a) - (c) in Section II Answer Booklet 1.
(a)
The neutron, as a particle found in the nucleus of all atoms, had been suggested a long
time before they were actually identified. Today they can be successfully used as
probes to determine the structure of matter. Describe the experiment that was used to
identify the neutron.
3
(b)
What are the main advantages of using neutrons as a probe to explore the structure of
matter.
2
(c)
The LHC (Large Hadron Collider), a particle accelerator, has cost an estimated nine
billion dollars. Justify the expenditure on this instrument.
5
Answer parts (d) - (f) in Section II Answer Booklet 2.
(d)
(e)
(f)
During the late 1930s, Fermi continued to work on the nucleus. His work led to the
creation of the first nuclear fission reactor in Chicago during 1942. The reactor
consisted of a ‘pile’ of graphite moderator, uranium fuel and cadmium control rods.
(i)
What is nuclear fission?
2
(ii)
What is the function of the moderator in the reactor?
2
(iii)
How did the cadmium rods control the rate of fission?
2
Bohr’s model was used to explain the hydrogen spectrum and to resolve some of the
problems of the Rutherford-Bohr model.
(i)
Discuss how Bohr proposed to overcome the problems of the Rutherford-Bohr
model.
2
(ii)
Outline two problems associated with the Bohr model.
2
With reference to the standard model of matter, sketch a diagram of the helium-4 atom
showing the constituents and the various fundamental forces involved.
5
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Question 37 The Age of Silicon (25 marks)
Answer parts (a) - (d) in Section II Answer Booklet 1.
(a) Outline the similarities and differences between an integrated circuit and a transistor.
3
(b) Explain how the structure of a light-emitting diode (LED) uses the properties of
semiconducting materials.
2
(c) Describe the role of transducers as an interface between the environment and an
electronic system.
4
(d) What properties of silica make it a suitable material for use in optical fibres?
3
Answer parts (e) - (g) in Section II Answer Booklet 2.
(e) The diagram below shows a typical potential divider circuit.
12 v
R
X
R
0v
(i) If R1 is 450 Ω and R2 is 800 Ω what is the voltage at X?
1
(ii) Outline why potential divider circuits are necessary in electronic circuits.
2
(f) Draw a diagram of an inverting and a non-inverting operational amplifier explaining the
differences between them.
4
(g) (i) Draw examples of AND, OR and invertor gates with corresponding truth tables.
3
(ii) Draw a circuit using gates to make a half adder. Include a truth table in your answer.
3
End of paper
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