Download AQA PHY1 PRACTICE PAPER RD2 (1¼ Hrs)

AQA PHY1 PRACTICE PAPER RD2
1.
(a)
(1¼ Hrs)
Name the constituent of an atom which
(i)
has zero charge,
.................................................................................................................................................
(ii)
has the largest charge to mass ratio,
.................................................................................................................................................
(iii)
when removed leaves a different isotope of the element.
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(b)
An  particle is the same as a nucleus of helium,
The equation
229
90
Th
X
Y
4
2
He.
Ra
+

represents the decay of thorium by the emission of an  particle.
Determine
(i)
the values of X and Y, shown in the equation,
X = .....................
Y = .....................
(ii) the ratio
mass of XY Ra nucleus
mass of  particle
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[Total 6 marks]
2. (a)
(i)
How do hadrons differ from all other subatomic particles?
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(ii)
Give the quark composition of the following particles.
neutron ................................................................................................................................
neutral pion .........................................................................................................................
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AQA PHYA1 Practice Paper RD2
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(iii) Classify the following as leptons, baryons or mesons.
kaon ...............................................................
muon ...........................................................
[5]
(b)
Which is the most stable baryon?
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(c)
This table may be useful in answering the questions which follow.
particle
baryon number
lepton number
strangeness
–
0
0
0
p
1
0
0
p
–1
0
0
e–
0
1
0
e+
0
–1
0
ve
0
–1
0
The particle X, which is a strange particle, decays in the following way:
X  – + p
(i)
State whether X is a meson, a baryon or a lepton.
.................................................................................................................................................
(ii)
Use conservation laws to decide whether each of the following decays of the – is possible.
Give a reason for your answer.
–  e+ + e
(A)
Is this decay possible? ........................
reason .........................................................................................................................
π –  p  e–  e
(B)
Is this decay possible? ........................
reason .....................................................................................................................[5]
[Total 11 marks]
AQA PHYA1 Practice Paper RD2
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3.
(a)
Explain what happens to electrons in hydrogen atoms when a spectrum, such as that
represented below, is produced.
You may be awarded marks for the quality of written communication in your answer.
intensity of
electromagnetic
radiation
wavelength
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(b)
A fluorescent tube is filled with mercury vapour at low pressure. In order to emit light the mercury
atoms must first be excited.
(i)
What is meant by an excited mercury atom?
...........................................................................................................................................................
...........................................................................................................................................................
(ii)
Describe the process by which mercury atoms become excited in a fluorescent tube.
...........................................................................................................................................................
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.......................................................................................................................................................[3]
(c)
What is the purpose of the coating on the inside surface of the glass in a fluorescent tube?
...........................................................................................................................................................
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.......................................................................................................................................................[2]
AQA PHYA1 Practice Paper RD2
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(d)
The lowest energy levels of a mercury atom are shown below. The diagram is not to scale.
energy / J × 10 –18
(i)
n=4
–0.26
n=3
n=2
–0.59
–0.88
ground state n = 1
–2.18
Calculate the frequency of an emitted photon due to a transition, shown by an arrow, from
level n = 4 to level n = 3.
.................................................................................................................................................
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(ii) Draw a line on the diagram to show a transition which emits a photon of a longer wavelength
than that emitted in the transition from level n = 4 to level n = 3.
[3]
[Total 12 marks]
4.
(a)
(i)
Explain what is meant by duality of electrons.
.................................................................................................................................................
.................................................................................................................................................
(ii)
Give one example of each type of behaviour of electrons.
.................................................................................................................................................
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(b) Electrons, of mass m and charge e, are accelerated from rest through a potential difference, V, and
acquire a kinetic energy of ½ m  2, where  is the final velocity of the electrons.
Show that:

h
2meV
where h is the Planck constant and  is the electron wavelength.
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(Total 6 marks)
AQA PHYA1 Practice Paper RD2
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5.
A very high resistance voltmeter reads 20V when connected across the terminals of a d.c. power supply.
The high resistance meter is disconnected and a second voltmeter of resistance 1.0 k  is then connected
across the supply. The second meter gives a reading of 16 V.
(i)
State the e.m.f. of the power supply.
...........................................................................................................................................................
(ii)
Calculate the current which flows through the second meter.
...........................................................................................................................................................
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(iii)
Calculate the internal resistance of the power supply.
...........................................................................................................................................................
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(iv)
Show that the current is equal to 0.080 A when the supply is short circuited.
...........................................................................................................................................................
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[Total 5 marks]
6.
The diagram below shows a series circuit containing resistors and silicon diodes.
3 k
A
D1
12 V
B
D2
5 k
C
(a)
Calculate
(i)
the voltage between A and C,
.................................................................................................................................................
.................................................................................................................................................
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AQA PHYA1 Practice Paper RD2
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(ii)
the voltage between B and C.
.................................................................................................................................................
.................................................................................................................................................
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[4]
(b)
A student connects diode D2 the opposite way round to that shown in the diagram above.
State, giving reasons,
(i)
the new voltage between A and C,
.................................................................................................................................................
.................................................................................................................................................
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(ii)
the new voltage between B and C.
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[Total 7 marks]
7.
The mean kinetic energy of an ideal gas molecule is
and k is the Boltzmann constant.
(a)
3
2
kT, where T is the absolute temperature of the gas
Estimate the mean kinetic energy of a molecule at 2 K.
...........................................................................................................................................................
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(b)
Calculate the de Broglie wavelength of an atom of He 4 which has kinetic energy equal to your
estimate in part (i).
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AQA PHYA1 Practice Paper RD2
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(c)
Comment on the significance of your answer in relation to the superfluid behaviour of liquid
helium.
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[Total 6 marks]
8.
The diagram shows a trace on the screen of an oscilloscope. The Y-sensitivity of the oscilloscope is set at
5.0 V per division and the time base is set at 0.50 ms per division.
0V
(a)
For the trace, determine
(i)
the maximum positive value of potential difference,
(ii)
.................................................................................................................................................
the maximum negative value of potential difference,
.................................................................................................................................................
(iii)
the frequency of the signal.
.............................................................................................................................................[4]
(b)
The trace shows the variation in the potential difference across a 100  resistor. Calculate the
energy dissipated in the resistor
(i)
for the first 1.00 ms,
.................................................................................................................................................
(ii)
.................................................................................................................................................
between 1.00 ms and 1.50 ms,
.................................................................................................................................................
.................................................................................................................................................
(iii)
in one cycle,
.................................................................................................................................................
(iv)
in one second.
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[5]
[Total 9 marks]
AQA PHYA1 Practice Paper RD2
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9.
A heating element, as used on the rear window of a car, consists of three strips of a resistive material,
joined, as shown in the diagram, by strips of copper of negligible resistance. The voltage applied to the
unit is 12 V and heat is generated at a rate of 40 W.
+ 12 V
0V
copper
resistive material
(a)
(i)
Calculate the total resistance of the element.
...........................................................................................................................................................
...........................................................................................................................................................
(ii)
Hence show that the resistance of a single strip is about 11 .
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[5]
(b)
If each strip is 2.6 mm wide and 1.1 mm thick, determine the length of each strip.
resistivity of the resistive material = 4.0 × 10–5  m
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[Total 8 marks]
[Paper Total 70 marks]
AQA PHYA1 Practice Paper RD2
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