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05.04.09 sundayherald
PHYSICS
STANDARDGRADE: GENERAL LEVEL (2008 PAPER,SELECTED QUESTIONS;)
1.
When a student whistles a note into a microphone connected to an
oscilloscope, the following pattern is displayed.
6.
A student is listening to a radio.
(a) Complete the passage below using words from the following list.
sound
amplifier
light
microphone
aerial
battery
tuner
decoder
electrical
The ........................ of a radio receiver detects signals from many
different stations and converts them into electrical signals.
The ........................ selects one particular station from many.
Without changing the oscilloscope controls, another student whistles a quieter
note of higher frequency into the microphone. Which of the following shows
the pattern which would be displayed on the screen?
A
B
The ........................ increases the amplitude of these electrical signals.
The energy required to do this is supplied by the ....................... .
C
The loudspeaker in a radio receiver converts ....................... energy into
........................ energy.
D
3
(b) Electrical signals are displayed as waves on an oscilloscope.
E
6 centimetres
2.
The weather information satellite NOAA-15 has a period of 99 minutes and
Answer
an orbital height of 833 kilometres.
The geostationary weather information satellite Meteosat has a period of
1440 minutes and an orbital height of 35 900 kilometres.
Which of the following gives the period of a satellite that has an orbital height
of 20 000 kilometres?
A
D
3.
4.
B
E
99 minutes
1750 minutes
C
720 minutes
Which row in the table describes the correct configuration for an atom?
orbiting the nucleus
inside the nucleus
A
protons only
electrons and neutrons
B
electrons and protons
neutrons only
C
neutrons and protons
electrons only
D
electrons only
neutrons and protons
E
neutrons only
electrons and protons
7.
A football match is being broadcast live from Dundee. Signals from the
football stadium are transmitted to a television studio in Glasgow via a relay
station on top of a nearby hill.
At the relay station, a curved reflector is placed behind a detector of the
television signals.
(a) (i) State the purpose of the curved reflector.
(ii) Complete the diagram below to show the effect of the curved
reflector on the signal at the relay station.
detector
Answer
A light
1 second
The time taken for
to reach usBfrom
the Sun is approximately
8 seconds
C
1
minute
D
8
minutes
B 8 seconds
A 1 second
C 1 minute
D
5.
83 minutes
1440 minutes
12 centimetres
(i) Calculate the wavelength of the waves.
(ii) Calculate the amplitude of the waves.
8 minutes
E
signals from
stadium
1 hour.
(b) During the match, strong winds cause the reflector to move to a new
position as shown.
Two objects are dropped from the same height. Both objects fall freely.
Object X has a mass of 10 kilograms.
Object Y has a mass of 1 kilogram.
Object X accelerates at 10 metres per second per second.
The acceleration of object Y, in metres per second per second, is
A
0.1
B
detector
signals from
stadium
1.0
C
10
D
100
E
1000.
State the effect this has on the signal received at the detector.
Answer
[Turn over
sundayherald 05.04.09
8.
9
Marks
A
drummer
a rock
band
is exposed
sound
lev of up to
Two household electrical appliances, a 1500 watt electric iron and a 300 watt 10. (a) A) Marks
drummer
in in
a rock
band
is exposed
to to
sound
levels
to 110 decibels.
uplighter lamp, are shown below.
Explain why ear protectors are used to reduce the sound level
flex covered in
experienced by the drummer.
heat-resistant material
brightness
adjustment
metal stand
metal base
flex covered
with plastic
heat setting dial
(a) The brightness of the uplighter lamp can be changed.
State an electrical component that could be used to change the brightness
of the uplighter lamp.
(b) Explain why the flex for the iron is covered with a heat-resistant material.
(c) A cross-section of the flex for each appliance is shown.
neutral
earth wire
neutral
wire
wire
earth wire
live wire
electric iron
insulation
(b) A medical researcher is measuring the upper range of hearing of people
in different age groups.
The bar graph shows the frequencies of sound detected by these people.
100
90
80
70
60
% of people 50
40
30
20
10
0
insulation
live wire
uplighter lamp
Two identical lamps are connected to a 6.0 volt battery as shown in circuit 1.
6.0 volts
lamp 1
circuit 1
Lamp 1
12 14 16 18
frequency in kilohertz
Marks
1.A
2.C
3.D
4.D
5.C
6.
lamp 2
(a) The battery supplies a current of 0.40 ampere to the circuit.
Complete the following table to show the current in each lamp and the
voltage across each lamp.
10
20
(i) State two conclusions which can be made from this bar graph about
the hearing of different age groups.
(ii) What name is given to sound frequencies greater than 20 kilohertz?
(i) State the colour of the insulation on the live wire.
(ii) State the purpose of the earth wire.
(iii) Explain why the wires in the flex for the electric iron are thicker
than those for the uplighter lamp.
9.
15 – 20 yrs
35 – 40 yrs
55 – 60 yrs
7.(a)
Lamp 2
ANSWERS
(a)•Theaerialofaradioreceiverdetectssignalsfrommanydifferentstationsand
convertsthemintoelectricalsignals.
•Thetunerselectsoneparticularstationfrommany.
•Theamplifierincreasestheamplitudeoftheseelectricalsignals.
•Theenergyrequiredtodothisissuppliedbythebattery.
•Theloudspeakerinaradioreceiverconvertselectricalenergyintosoundenergy.
(b)(i)6cm
(ii)3cm
(i)increases(amplitudeof)receivedsignalORcollects/gathersmoresignals
collects/gathers more signals
(ii)
(ii)
Current
(amperes)
Voltage
(volts)
(b) The two lamps are now connected as shown in circuit 2.
(b)
8.
circuit 2
lamp 1
lamp 2
9.
(amplitudeof)signalisreduced
a)variableresistor/resistance
(b)heatfromironcouldmeltflex
(c)(i)brown
(ii)safetydeviceORpreventsshock/electrocution
(iii)(requires)morecurrentOR(requires)morepowerORmoreenergy
(a)
Current (amperes)
State the voltage of the battery required to light the lamps with the same
brightness as in circuit 1.
Voltage (volts)
(c) In which of the two circuits, circuit 1 or circuit 2, would lamp 2 still be
on when lamp 1 is removed?
Lamp 1
Lamp 2
0·2
0·2
6
6
(b) 12 V
(c) circuit 1
10.
(a) (sound levels above 80dB) can damage hearing
(b) (i) • All age groups can hear sounds of frequencies up to 12 kHz.
• Younger people can hear a greater range of frequencies than older age
groups.
(ii) ultrasound/ultrasonic
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05.04.09 sundayherald
HIGHER (2008 PAPER,SELECTEDQUESTIONS;)
4. The total mass of a motorcycle and rider is
250 kg. During braking, they are brought to
−1
rest from a speed of 16.0 m s in a time of
.
10 0 s.
1. Which row in the table is correct?
Scalar
Vector
A
distance
work
B
weight
acceleration
C
velocity
displacement
D
mass
momentum
E
speed
time
The maximum energy which could be
converted to heat in the brakes is
A
D
2000 J
40 000 J
B
E
4000 J
64 000 J .
C
32 000 J
5. A shell of mass 5.0 kg is travelling horizontally
with a speed of 200 m s−1. It explodes into two
parts. One part of mass 3.0 kg continues in the
original direction with a speed of 100 m s−1.
2. A javelin is thrown at 60 ° to the horizontal with
a speed of 20 m s−1.
The other part also continues in this same
direction. Its speed is
150 m s−1 B
350 m s−1 E
A
D
−1
20 m s
−1
200 m s
−1
700 m s .
C
−1
300 m s
6. The graph shows the force which acts on an
object over a time interval of 8 seconds.
force/N
12
60 °
10
The javelin is in flight for 3.5 s.
Air resistance is negligible.
The horizontal distance the javelin travels is
A
35.0 m
B
60.6 m
D
121 m
E
140 m.
C
8
6
70.0 m
4
2
3. Two boxes on a frictionless horizontal surface
are joined together by a string. A constant
horizontal force of 12 N is applied as shown.
2.0 kg
4.0 kg
12 N
The tension in the string joining the two boxes
is
84.00 N
C
6
0N
N D
B
N
C
6.0 N
A
2.0
D
8.0 N
E
12 N .
ANSWERS
1.D 2.A 3.B 4.C 5.D 6.C 7.D 8.E 9.E 10.D 11.A 12.B
0
0
2
4
6
8
10
time/s
The momentum gained by the object during
this 8 seconds is
A A 12 kg
12 m s−1 B
44 kg m s−1
32 kg m s−1 C
−1
−1
D
52 kg m s
E
72 kg m s .
7. One pascal is equivalent to
A
1 Nm
B
1 N m2
C
1 N m3
D
1 N m–2
E
1 N m–3.
sundayherald 05.04.09
11
8. An electron is accelerated from rest through a
potential difference of 2.0 kV.
11. A resistor is connected to an a.c. supply as
shown.
The kinetic energy gained by the electron is
B
8.0 × 10–20 J
A
8.0 × 10–23 J
3.2 × 10 J
–16
3.2 × 10 J.
–19
C
E
D
1.6 × 10
–16
R
J
"
a.c. ammeter
The supply has a constant peak voltage, but its
frequency can be varied.
9. The e.m.f. of a battery is
A
the total energy supplied by the battery
B
the voltage lost due to the internal
resistance of the battery
C
the total charge which passes through the
battery
D
the number of coulombs of charge passing
through the battery per second
E
the energy supplied to each coulomb of
charge passing through the battery.
10. The diagram shows the trace on an oscilloscope
when an alternating voltage is applied to its
input.
The frequency is steadily increased from 50 Hz
to 5000 Hz.
The reading on the a.c. ammeter
A
remains constant
B
decreases steadily
C
increases steadily
D
increases then decreases
E
decreases then increases.
12. An ideal op-amp is connected as shown.
10 kΩ
1 div
5 kΩ
1 div
V1
Vo
The graph shows how the input voltage, V1,
varies with time.
V1 /V
+0.2
0
The timebase is set at 5 ms/div and the Y-gain
is set at 10 V/div.
Which row in the table gives the peak voltage
and the frequency of the signal?
Peak voltage/V
A
7.1
time
B
14
50
C
20
20
Vo /V
Vo /V
A +0.4
B
0
Frequency/Hz
20
time
Which graph shows how the output voltage, Vo,
varies with time?
time
Vo /V
Vo /V
C
time
–0.4
time
–0 4
0
D
+0.1
0
time
0
–0.1
time
Vo /V
E +0.2
D
E
20
40
50
50
time
–0.2