SECOND TERM EXAMINATION (2000-2001)
SECONDARY VII PHYSICS
PAPER II
Name:_____________________(
)
Date: 25-2-2000
Time: 3 hours
Class: S.7( )
No. of pages: 16
Section A
There are 45 questions in this section. Answer ALL questions. You should spend about 1 hour and
45 minutes in this section. Where necessary, take g to be 10 ms-2 and take c to be 3 x 108 ms-1.
1.
The arrangement shown is used to find the output power of an electric
motor. The wheel attached to the motor's axle has a circumference of
0.5 m and the belt which passes over it is stationary when the weights
have the values shown in the diagram. If the wheel makes 20
revolutions per second, the output power is
A. 200 W
B. 300 W
C. 500 W
D. 600 W
E. 700 W
2.
A mass m is attached to a string wound around the axle of a
flywheel of radius R. The radius of the axle is r. The mass,
after falling through a vertical distance h, strikes the ground
at a speed v. Neglect all effects due to air resistance and
friction. Which of the following statements is /are true?
(1) The loss in gravitational potential energy of mass m is
equal to the gain in rotational kinetic energy of the
flywheel.
2h
(2) The time for the mass to fall a distance h is
.
v
(3) The angular acceleration of the flywheel is
A.
B.
C.
D.
E.
v2
.
2 rh
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
3.
Two wooden blocks A and B of the same mass are
connected by a string which passes over a smooth
fixed pulley as shown. The blocks are at rest. The
maximum friction between any two surfaces is 2 N. If
a force F parallel to the plane is applied to A, find its
minimum value for moving A.
A. 2 N
B. 4 N
C. 6 N
D. 8 N
E. cannot be determined because the mass of each block and the angle of inclination are not
given.
4.
Racing tracks for cars are banked on the corners at an angle to the horizontal. Which of the
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following is a possible reason for this design feature?
(1) To reduce the frictional force between the car and the track necessary to prevent skidding.
(2) To reduce the radius of curvature of the path which a car travelling at a given speed can
safely follow.
(3) To increase the component of the weight of the car towards the centre of its path.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
5.
A simple pendulum is displaced an angle  and is released from rest. If T is the tension in the
string and m is the mass of the bob, which of the following statements is/are correct?
(1) When the bob passes through its lowest position, the tension T is equal to mg.
(2) At the moment when the bob is released, T cos  = mg.
(3) The restoring force of the harmonic motion is mg sin .
A.
B.
C.
D.
E.
6.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
A ball bounces elastically up and down on the ground in the vertical direction. Which of the
following graphs best describes the variation of its momentum p with time t?
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7.
Two pendulums, X and Y, are identically coupled to a much more massive pendulum, Z. The
length of Z is varied. Graphs of the amplitude of oscillation of X and Y against the length of Z
are shown in the diagram. Which of the following is correct?
(1) The pendulums X and Y have equal length.
(2) Y is more heavily damped than X.
(3) X and Y will always vibrate in phase with Z.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
8.
A star rotating about an axis through its centre runs out of nuclear fuel and collapses. The
radius decreases by 103 times. Assuming no mass loss and the densities before and after
collapses are uniform. Which of the following is true?
A. Its angular speed increases by 103 times.
B. Its density increases by 103 times.
C. Its angular momentum increases by 103 times.
D. Its kinetic energy increases by 106 times.
E. The acceleration due to gravity on its surface increases by 103 times.
9.
The velocity of escape from the earth is V0. For a planet with radius three times that of the
earth and with density twice that of the earth, the velocity of escape from the planet would be
A.
2 V0
B.
6 V0
C.
2 3 V0
D.
3 2 V0
E.
2 6 V0
10. Which of the following statements is INCORRECT?
A. Gravitational field lines are perpendicular to equipotential lines.
B. Gravitational field strength is the negative of potential gradient.
C. Along the line joining the earth and the moon, the gravitational potential is zero at a point
where the resultant gravitational field is zero.
D. When a spacecraft moves along a line of equipotential, it acquires no change in potential
energy.
E. An astronaut in a spacecraft feels weightless when the spacecraft falls towards the earth
with the engine turned off.
11. The diagram shows the interference pattern in a ripple tank when the probes P and Q are
vibrating in phase and at a frequency of 10 Hz. The lines of the pattern are equally spaced
between P and Q and are 1.0 cm apart. The speed of the water waves in the ripple tank is
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A.
B.
C.
D.
E.
0.025 ms-1
0.050 ms-1
0.10 ms-1
0.20 ms-1
0.40 ms-1
12. The figure shows a section of a continuous plane polarized radio wave travelling along the
x-direction. The vectors in the y-direction represent the varying electric field and those in the
z-direction represent the varying magnetic field. For the reception of the wave, two types of
aerials available are straight metal rods and circular metal loops. How should each type of
aerials be oriented for maximum reception of the radio wave?
Orientation of straight
Orientation of circular
metal rods
metal loops
A.
The length of the rod in
The plane of the loop in
x-direction.
the x-y plane.
B.
The length of the rod in
The plane of the loop in
y-direction.
the x-z plane.
C.
The length of the rod in
The plane of the loop in
z-direction.
the y-z plane.
D.
The length of the rod in
The plane of the loop in
x-direction.
the y-z plane.
E.
The length of the rod in
The plane of the loop in
y-direction.
the x-y plane.
13. A diffraction grating ruled with 5000 lines per cm is illuminated normally by white light. If the
wavelengths for yellow light and violet light are 600 nm and 400 nm respectively, which of
the following statements is false?
A. The central image is white.
B. The violet end of the first-order spectrum is closer to the central image than is the red end
of the first-order spectrum.
C. The second-order image of yellow light coincides with the third order image of violet
light.
D. The angular displacement of the second-order image of yellow light from the central
image is sin-1 0.6.
E. There is no fourth-order image for violet light.
14. When monochromatic light is incident normally on a wedge-shaped thin film, an interference
pattern may be seen by reflection. Which of the following changes would increase the number
of fringes per unit length as seen by an observer?
(1) increasing the wavelength of the light
(2) increasing the angle of the wedge
(3) increasing the refractive index of the film material
A.
B.
C.
D.
E.
(1), (2) and (3)
(1) and (2) only
(2) and (3) only
(1) only
(3) only
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15. When two notes of nearly equal frequencies f1 and f2, with f2 > f1, are sounded together, beats
are heard. Beats are periodic variations in
A. pitch, with beat frequency (f2 - f1).
B. pitch, with beat frequency ½ (f1 + f2).
C. loudness, with beat frequency (f2 - f1).
D. intensity, with beat frequency ½ (f2 - f1).
E. intensity, with beat frequency ½ (f1 + f2).
16. Two loudspeakers are connected to the same signal source of negligible impedance At a point
equidistant from the two loudspeakers, the intensity level of the sound produced is 30 dB
when one of the loudspeakers is turned on. If the other loudspeaker is also turned on, the
intensity level of the sound at that point will be
A. 33 dB
B. 36 dB
C. 60 dB
D. 63 dB
E. 67 dB
17. A sound source S approaches an observer O at a constant speed v. Speed of sound in air is c.
Which of the following statements is/are correct?
(1) The velocity of the sound wave relative to the observer is c + v.
(2) The frequency of the source as heard by O increases linearly with time as S approaches
O.
(3) The sound appears louder and louder as S approaches O.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
18. The surface of a material of refractive index 2.0 is coated with a thin film of liquid of
refractive index 1.5 and thickness 300 nm. White light falls normally on the thin film. Which
of the following light wavelengths (in air) is not reflected from the thin film?
A. 300 nm
B. 360 nm
C. 400 nm
D. 450 nm
E. 900 nm
19. When parallel light is incident at the Brewster angle in air on the surface of a glass block,
which of the following statements is/are correct?
(1) The reflected ray is plane-polarised.
(2) The refracted ray is plane-polarised.
(3) The incident ray and the reflected ray are at right angles to each other.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
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20. A projector lens produces on a screen a clear, enlarged image of a slide transparency. In which
case could a clear image with greater magnification be obtained?
Screen Movement
Lens Movement
A.
farther away
closer to the slide
B.
farther away
none
C.
closer
away from the slide
D.
none
closer to the slide
E.
closer
closer to the slide
21. An ideal gas inside a container without thermal insulation is compressed very slowly to 70 %
of its original volume. While the gas is being compressed, there is a heat energy transfer of
5000 J. Which of the following statements is/are correct?
(1) Heat energy is transferred out of the system.
(2) The internal energy increases by 5000 J.
(3) Work is done by the gas to overcome the external pressure.
A.
B.
C.
D.
E.
(1) only
(3) only
(1) and (2) only
(2) and (3) only
(1), (2) and (3)
22. Identical containers A and B contain oxygen (O2) and
hydrogen (H2) respectively. Both gases are at room
temperature and atmospheric pressure. Which of the
following statements is/are true?
In both containers,
(1) the number of gas molecules is the same;
(2) the r.m.s. speed of H2 molecules is greater than
that of O2 molecules;
(3) the frequency of collision of gas molecules with the walls
of container is the same.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
23. A fire extinguisher is filled with water up to a level 0.5 m below
its nozzle as shown. If water is ejected from the nozzle at a
speed of 30 ms-1, what is the gas pressure in excess of the
atmospheric pressure? (Density of water = 103 kg m-3.)
A. 1.50 x 105 Pa
B. 1.55 x 105 Pa
C. 4.45 x 105 Pa
D. 4.50 x 105 Pa
E. 4.55 x 105 Pa
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24. The figure shows a simplified model of the force between two
atoms in a solid plotted against their distance of separation.
Which of the following statements is/are true?
(1) The equilibrium separation of the atoms is r2.
(2) The stiffness of the solid depends on the slope of the curve near r2.
(3) The energy required to separate the two atoms is ½ [ F2 (r2 - r1) + F1 (r4 - r2) ]
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
25. In a circuit with a vibrating reed switch, a 2 F capacitor is charged from a battery of e.m.f. 12
V and completely discharged through a resistor with a frequency of 25 Hz. The average power
dissipated as heat in the resistor is
A. 24 W
B. 57.6 W
C. 144 W
D. 0.6 mW
E. 3.6 mW
26. A steady potential difference V is applied across a coil of inductance
L and resistance R, connected to a switch S, as shown. After closing
the switch S, the current increases and takes time t to reach half its
steady maximum value. The time t can be shortened by
(1) inserting a piece of soft iron inside the solenoid.
(2) applying a higher potential difference to the circuit.
(3) adding a resistor in series with the coil.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
27. Particles A and B moving at the same speed enter a square region of uniform magnetic field as
shown. Particle A leaves at X while particle B leaves at Y. If the charge to mass ratio of particle
A is k and the period of particle A is T, what is the period of particle B?
A. T
B.
C.
D.
E.
2T
2T
kT
2
2T
k
-7-
28. As observed from above, a metal disc rotates clockwise
steadily about a vertical axle passing through its centre with
part of its plane cutting through a magnetic field, the
direction of which is pointing vertically downwards. A
resistor R is connected to the disc through two brushes P
and Q. P touches the edge of the disc and Q makes contact
with its vertical axle. Which of the following is/are correct?
(1) A current flows from Q to P through the disc.
(2) The e.m.f. induced across P and Q is proportional to the area of the disc.
(3) The potential at Q is higher than that at P.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
29. The diagram illustrates the principle of an ohmmeter converted from a galvanometer.
Unknown resistors are connected across XY.
(1) The value of R should not be small compared with the unknown resistors.
(2) If X and Y are short-circuited and the pointer of the galvanometer stays mid-way between
P and Q, then R should be decreased during "zero-adjustment".
(3) If the galvanometer is correctly calibrated in ohm, the scale is non-linear.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
30. In the circuit shown, reading of voltage and current were recorded for different values of
supply frequency. The readings are as shown.
Reading on meter A in
mA (r.m.s.)
Reading on meter V in
V (r.m.s.)
Frequency of supply
in Hz
5 mA
2 mA
3 mA
5V
5V
5V
100 Hz
500 Hz 1000 Hz
Which of the following components could be connected
between the terminals of box X?
A. a capacitor and an inductor in parallel
B. a resistor and an inductor in parallel
C. a capacitor and a resistor in series
D. a capacitor and an inductor in series
E. a capacitor and a resistor in parallel
-8-
31. A charged particle is fired between a pair of parallel plates as shown in the diagram. On
leaving the plates, it has been deflected downwards by 1 unit. A different charged particle,
which has double the charge and four times the mass of the first, is fired with the same
velocity between the plates. It will be deflected by
A.
B.
C.
D.
E.
¼ unit
½ unit
1 unit
2 units
4 units
32. The coil of the galvanometer shown in the diagram is suspended at the end of a fibre and is
wound on a light former. Which of the following factors alone will increase current sensitivity
of the galvanometer?
(1) Increase the current flowing into the coil.
(2) Keeping the number of tuns of the coil the same, replace the
wire with a thicker wire.
(3) Replace the fibre with another one of lower restoring torque.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
33. The diagram shows a plan view of four long straight current-carrying
wires. The wires are parallel to each other and are perpendicular to the
plane of the page, passing through the points P, Q, R, S at the corners
of a square. X is the intersection of the diagonals of the square.
The magnetic flux density at the point X is zero. In order for this to be the
case, which of the following conditions must hold?
(1) The current in P must be in the same direction as that in R.
(2) The currents in all four wires must be of the same magnitude.
(3) The currents in all four wires must be in the same direction.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
34. When a steady state is reached, the current delivered by the battery is
A.
B.
C.
D.
E.
zero.
4.0 A
5.0 A
5.3 A
8.0 A
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35. Two coaxial solenoids P and Q are arranged as shown. The cross-sectional areas of P and Q
are A1 and A2 respectively. P contains N1 turns while Q contains N2 turns. Q is now connected
to a power supply so that the current through it rises at a uniform rate S. The maximum e.m.f.
induced in P is
A.
B.
C.
D.
E.
μ0N1N2A1S / L
μ0N1N2A2S / L
μ0N1N2A1S / L2
μ0N1N2A2S / L2
zero
36. A resistor R and a capacitor C are connected in series with an a.c. supply. The r.m.s. applied
voltage and the r.m.s. current are V and I, respectively. If the resistance of R is equal to the
reactance of C, the power consumed in the circuit will be
A. IV / 4
B.
IV / 3
C.
IV / 2
D.
IV / 2
E.
3 IV / 2
37. The diagram shows part of a circuit which carries a current of 1 A from X to Y through a cell
of e.m.f. 4 V and internal resistance 1 Ω. The potential difference between X and Y is
A. 1 V
B. 2 V
C. 3 V
D. 4 V
E. 5 V
38. A battery, a resistor and a parallel plate capacitor are connected in series. If the plates of the
capacitor shown in the diagram are brought closer together, which of the following quantities
will increase in magnitude?
(1) The charge of both plates.
(2) The field between the plates.
(3) The potential difference across the plates.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
39. A photocell has a steady p.d. maintained between its cathode and anode. If its distance from a
monochromatic light source is increased from 1 m to 2 m the electrons emitted from the
cathode would
(1) possess one quarter of the previous energy
-10-
(2) reach the collector with one quarter of the previous speed
(3) be emitted at one quarter of the previous rate.
Which of the above statements is/are correct?
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
40. The trace shown is obtained on the screen of an
oscilloscope. From this it can be inferred that
(1) a linear time base is applied to the X plates
(2) the frequency in the Y direction is 3/2 times the
frequency in the X direction
(3) a sinusoidal signal is applied to the Y plates
Which of the above statements is/are correct?
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
41. The diagram represents part of the energy levels for a
valence electron of a certain atom. λ1, λ2 and λ3 are the
wavelengths of the radiations emitted when the electron
jumps between the levels of energy E1, E2 and E3 as
indicated by the arrows. Which of the following statements
is/are correct?
(1)
1
1
=
1
2
+
1
3
(2) The frequency of the radiation of wavelength λ1 is the
greatest.
(3) If λ1 is a wavelength in the ultra-violet, then λ2 could be a wavelength in the visible
spectrum.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
42. In the diagram shown, an α-source is placed over an
ionization chamber. A saturation current I flows
through resistor R of resistance 109 Ω when the p.d.
between the electrodes is 60 V. The p.d. across R is
then measured by a non-inverting amplifier circuit. A
voltmeter V connected across the output gives a
reading of 5 V. what is the value of I?
A. 1.0 x 10-10 A
B. 1.2 x 10-10 A
-11-
C.
D.
E.
1.0 x 10-9 A
1.2 x 10-9 A
6.0 x 10-8 A
43. The diagram shows the spectrum of X-rays emitted from an X-ray tube.
Which of the following statements about the spectrum is/are correct?
(1) If peaks appear in the spectrum, their
wavelengths are independent of the potential
difference across the tube.
(2) The cut-off wavelength is independent of the
material of the target in the tube.
(3) The continuous part of the spectrum is caused by
the slowing down of the electrons as they strike
the target.
A. (1), (2) and (3)
B. (1) and (2) only
C. (2) and (3) only
D. (1) only
E. (3) only
44.
14
C is used for the dating of a wooden archaeological specimen. Three measurements taken are
listed below:
Specimen
Count-rate
1 g sample of living wood
80 counts per minute
1 g sample of archaeological
40 counts per minute
specimen
no sample
20 counts per minute
Given that the half-life of 14C is 5700 years, what is the approximate age of the specimen?
A. 4200 years
B. 5700 years
C. 8550 years
D. 9000 years
E. 11400 years
45. Which of the following is/are indicator(s) of the binding energy per nucleon of an isotope?
(1) Stability of the isotope.
(2) Energy needed to split the nucleus into its individual nucleons.
(3) Neutrons to protons ratio.
A. (1) only
B. (3) only
C. (1) and (2) only
D. (2) and (3) only
E. (1), (2) and (3)
END OF SECTION A
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Section B
Answer any THREE questions from this section. Write your answers in the ANSWER book
provided
1. (a)
A rubber ball is dropped freely from a certain height onto a horizontal floor. It rebounds
to the same height after each bounce. In terms of the force acting, state two ways in
which the motion, although periodic, differs from simple harmonic motion.
(4 marks)
(b)(i) For a planet revolving the sun in a circular orbit of radius r and with period T, show that
r3 = KT2 where K is a constant.
(ii) Is the equation r3 = KT2, with the same constant K for the planet, also valid for a satellite
circling round the earth? Explain briefly.
(4 marks)
(c)
A boy riding on a bicycle goes round a corner. Draw a diagram to show the force(s)
acting on the boy and the bicycle as a system, and explain why the bicycle has to lean
with an angle to the vertical.
(4 marks)
(d)
Two identical cylinders, A and B, are held with their axes horizontal and at the same
height on slopes of the same inclination. When released from rest, cylinder A slides down
a smooth slope while cylinder B rolls down a rough slope without slipping. By using the
principle of conservation of energy, explain which cylinder has the greater linear speed
when reaching the bottom of the slopes. (No mathematical derivation is required) (4
marks)
2. (a)
The first law of thermodynamics may be written as
ΔU = Q + W
(i)
Explain the meaning of each term in the equation as it applies to the heating of a fixed
mass of gas at constant pressure thereby increasing the temperature of the gas.
(ii) Explain the effect on each term in the equation of producing an equal temperature change
in the same mass of gas at constant volume.
(iii) Hence explain which process, (i) or (ii), involves a greater heat transfer.
(6 marks)
(b)
(i)
A student stated that radioactive materials with a short half-life always have a high
activity.
What is meant by
(1) half-life,
(2) activity?
(ii) Discuss whether the student's statement is valid.
-13-
(4 marks)
(c)
What is the Bernoulli effect? Use the flow tube below to describe a simple demonstration
of the effect.
(4 marks)
(No mathematical derivation is required)
(d)
The diagram below shows the top-view of the flight of a tennis ball struck with a spin.
Describe, with reasons, the subsequent motion of the ball.
(2 marks)
3. (a)
State two of the principal differences between progressive waves and stationary waves.
(2 marks)
(b)
The diagram shows the apparatus used in an experiment to investigate the vibrations of a
length of copper wire. End A of the wire is attached to a vibrator which moves up and
down at the frequency of the signal generator. A load attached to end B keeps the wire in
tension. When the signal generator is adjusted to a particular frequency, a stationary wave
is obtained as shown.
(i) Explain why the mid-point of the wire is stationary.
(ii) Compare and contrast the motion of the wire at points P, Q and R.
(iii) The length AB of the copper wire used in the experiment is l and its mass is m; the mass
of the load is M. Find the lowest frequency f0 at which a stationary wave will be produced.
Draw a diagram of the wave.
(8 marks)
(c)
In another experiment the leads to the signal generator are removed from the vibrator and
connected to the wire near to points A and B so that an alternating current flows in the
wire. A horseshoe magnet is arranged to produce a horizontal magnetic field at right
angles to the wire near the mid-point.
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(i) Describe the additional force now experienced by the wire and explain how it arises.
(ii) State what you would expect to observe if the frequency of the alternating current were
gradually increased from zero to 3f0.
(iii) How could you use this experiment, suitably adapted, to measure the frequency of an
alternating voltage?
(6 marks)
4. (a)
Electromagnetic induction is the effect in which a changing magnetic field gives rise to
an e.m.f. in a conductor.
State (in words) the laws which define
(i) the magnitude of the induced e.m.f. and
(ii) the direction of the induced e.m.f.
(3 marks)
(b)(i) A copper disc is placed above an electromagnet so that
only part of the disc is placed between the poles. It is
found that the disc spins freely with the electromagnet
switched off, but quickly comes to rest when the
electromagnet is switched on. Explain these
observations.
(ii) Explain how the principle used above is applied in
moving-coil meters to prevent the pointer from
deflecting beyond the equilibrium position.
(6 marks)
(c)(i) Explain, with suitable diagrams, how to construct a transformer for supplying an
alternating voltage of 6 V from 220 V a.c. mains. State any assumptions and explain why
they are necessary.
(ii) Explain how the input current changes when a resistor is connected to the output
terminals.
(7 marks)
5.(a)
This question concerns an experiment to obtain the voltage transfer characteristics of an
amplifier. The amplifier is non-inverting; it has a voltage gain of 20 and uses an
operational amplifier with negative feedback. The operational amplifier used has a large
open loop gain and the circuit is operated from a -15 V — 0 — +15V supply.
(i) Draw a circuit diagram showing how two resistors can be connected to the operational
amplifier in order to obtain negative feedback. Suggest suitable values for the resistors.
(3 marks)
(ii) The input to the amplifier is to be a d.c. voltage, the value of which can be varied. Draw a
second circuit diagram showing how the power supply can be used to provide such an
input.
(2 marks)
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(iii) Sketch the graph of output voltage against input voltage which you would expect for the
amplifier you have drawn in (a). Label each axis and indicate the voltage values. Mark on
your graph the region in which the circuit could be used as an amplifier, and describe
how you would use the graph to confirm that the gain of the amplifier is 20.
(4 marks)
(b)
(c)
Explain why an op-amp in open-loop mode is suitable for using as a voltage comparator
in switching circuit, but is unsuitable for acting as an amplifier.
(4 marks)
Draw the circuit of a voltage follower using an ideal operational amplifier. Explain why
the output voltage follows the input voltage exactly.
(3 marks)
END OF PAPER
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CARMEL DIVINE GRACE FOUNDATION SECONDARY SCHOOL
SECOND TERM EXAMINATION (2000-2001)
SECONDARY VII PHYSICS
PAPER II (ANSWER)
Section A
1. B
2. D
3. C
4. B
5. B
6. D
7. B
8. D
9. D
10. C
11. D
12. E
13. E
14. C
15. C
16. B
17. E
18. B
19. D
20. A
21. A
22. C
23. E
24. C
25. E
26. E
27. C
28. A
29. A
30. A
31. B
32. D
33. A
34. E
35. B
36. C
37. E
38. B
39. E
40. C
Section B
1.
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41. E
42. B
43. A
44. D
45. A
m
p
p
p
p
p
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