Lisa chem

3. Data Sheet VCE Physics 2007 Year 11 Exam Unit 2
velocity; acceleration ∆x ∆v
1 v= ; a=
∆t ∆t
equations for constant acceleration v = u + at
1
x = ut + at 2
2
2
v = u + 2ax
2 2
1
x = (u + v)t
2
3 Newton's second law F = ma
4 Hooke's law F = −kx
5 elastic potential energy 1 2
kx
2
6 gravitational potential energy near the mg ∆h
surface of the Earth
7 kinetic energy 1 2
mv
2
8 voltage; power V = RI ; P = VI
9 resistors in series RT = R1 + R2
10 resistors in parallel 1 1 1
= +
RT R1 R2
11 charge on the electron q = −1.6 × 10−19 C
12 speed of light in vacuo 3.0 × 108 m s -1
13 acceleration due to gravity near the Earth’s surface 10 m s-2
Detailed study 3.1 Astrophysics
1 astronomical unit 1.5 ×1011 m
2 Parsec 3.1× 1016 m
3 light year 9.5 × 1015 m
4 Hubble constant (H) 74 km s -1 Mpc-1
v
H=
d
5 spectrum wavelength shift ∆λ v
=−
λ c
P r e f ix e s /U n its
p = p ic o = 1 0 −12
n = n a n o = 1 0 −9
µ = m ic ro = 1 0 − 6
m = m illi = 1 0 − 3
k = k ilo = 103
M = m ega = 10 6
G = g ig a = 1 0 −9
1 to n n e = 103 kg
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2

5. VCE Physics 2007 Year 11 Exam Unit 2
SECTION A – Core
Instructions for Section A
Answer all questions for both Areas of study in this section of the paper.
Area of study 1 - Movement
Questions 1 to 3 refer to the following information.
Figure 1 shows a speed – time graph for a car that stops at traffic lights and then moves away.
Speed (m s–1)
40
30
20
10
0
0 20 40 60 80
time (s)
Figure 1
Question 1
Calculate the initial speed of the car in km h–1.
km h –1
2 marks
Question 2
Calculate the distance, in m, traveled during the time the car is decelerating.
m
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 1

6. Question 3
Calculate the acceleration of the car, in m s –2 , in the time interval from 70 s to 80 s.
m s –2
2 marks
An object has a position – time graph as shown in Figure 2.
position
0 time
Figure 2
Question 4
Which one of the graphs, A – D in Figure 3, shows the corresponding velocity time graph for the
object?
A B
velocity velocity
0 time 0 time
C D
velocity velocity
0 time 0 time
Figure 3
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 2

7. Questions 5 and 6 refer to the following information.
Figure 4 shows the position and elapsed time of a bicycle rider starting from rest and uniformly
accelerating in a straight line.
0 1.0 s 2.0 s 3.0 s
Start 1.0 m 4.0 m 9.0 m
Figure 4 (not drawn to scale)
Question 5
Calculate the magnitude of the average velocity of the cyclist during the third second of travel.
m s –1
2 marks
Question 6
Calculate the magnitude of the acceleration over the 3.0 s time interval.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
m s–2
2 marks
A wooden box is first pulled across a horizontal steel plate as shown in Figure 5, diagram A. The
box is then pulled across the same steel plate while the plate is inclined at 200 to the horizontal as
shown in diagram B.
A B
F
F
200
Figure 5
Question 7
Which one of the following statements best describes how the normal force in diagram B compares
with the normal force in diagram A?
A The normal force is the same in both cases.
B The inclined box has a greater normal force.
C The inclined box has a lower normal force.
D The normal force cannot be determined from the information given.
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 3

8. A ball is thrown vertically upward with an initial velocity of 10 m s – 1 and an initial kinetic energy of
10 J.
Question 8
Which one of the diagrams, A - D in Figure 6 , best represents the kinetic energy versus time graph
of the ball while it is in the air.
A B
EK EK
t t
C D
EK EK
t t
Figure 6
2 marks
Question 9
Calculate the magnitude of the velocity of the ball when it has travelled half the distance.
m s –1
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 4

9. Questions 10 and 11 refer to the following information.
A bungee rope of unstretched length 50 m is designed to allow a person of mass 70 kg to come to
rest 85 m below the platform from which the person jumps.
Question 10
Calculate the energy stored in the rope when the jumper has come to rest.
Ignore the mass of the rope.
Gravitational field strength, g = 10 N kg –1 .
J
2 marks
Question 11
Calculate the magnitude of the gravitational potential energy lost in kJ by the jumper as they fall
from the platform to the lowest point..
kJ
2 marks
Blocks of 10 kg and 20 kg are connected with a rope as shown in Figure 7. The system is
accelerating to the right at 2.0 m s –2 on a smooth horizontal surface.
20 kg
T
10 kg
Figure 7
Question 12
Calculate the magnitude of the tension T, in N, in the rope connecting the 10 kg and the 20 kg
blocks.
N
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 5

10. A small toy car of mass 50 g is placed in a spring-loaded launcher, then released as shown in
Figure 8. A graph of force to compress the spring vs. distance compressed is shown in Figure 9.
Ignore friction and the mass of the spring when answering these questions.
Figure 8
Figure 9
Question 13
Calculate the magnitude of the work, in J, required to compress the spring by 0.080 m.
J
2 marks
The spring is compressed by 0.080 m and the toy car is placed in position.
Question 14
Calculate the speed of the car after the spring is released and the car moves across the floor.
m s –1
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 6

11. Figure 10 shows Barbara, of mass of 55 kg, performing a pole vault.
Figure 10
Barbara’s centre of mass rises 4.2 m during the vault and falls the same distance to the landing mat
after clearing the bar.
Question 15
Calculate Barbara’s vertical speed as she reaches the landing mat.
m s –1
2 marks
End of Area of Study 1
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 7

12. Area of Study 2 - Electricity
Questions 1 – 4 refer to the following information.
Linda and Gloria used the circuit shown in Figure 1 to determine the resistance of resistor, R. The
variable resistor, Y, was adjusted to give a range of readings on the voltmeter and the ammeter.
The battery can be assumed to have zero internal resistance.
9.0 V battery
A
Y
V
R
Figure 1
When the potential difference across R was 6.0 V, the current flowing through it was 0.20 A.
Question 1
Calculate the resistance, in Ω , of R.
Ω
2 marks
Linda and Gloria kept the current through resistor R at 0.20 A.
Question 2
Calculate the resistance, in Ω , of the variable resistor.
Ω
2 marks
Linda adjusts the resistance of Y so that it is different from the resistance of resistor, R.
Question 3
Which one of the following choices, A – D, is true for the current through component Y and the
potential difference across component Y?
choice Current through Y Potential difference across Y
A Different from that through R Different from that across R
B Different from that through R The same as that across R
C Almost the same as that through R Different from that across R
D Almost the same as that through R The same as that across R
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 8

13. The girls note that a constant current of 0.75 A flows through resistor R for 2.0 minutes.
Question 4
Calculate the amount of charge, in C, that flowed during this time.
C 2 marks
_____________________________________________________________________
The box shows the information panel on the back of a small fan heater.
240 V 50 Hz 2400W
Question 5
Which two of the statements, V – Z, are correct?
V. The current through the heater is 10 A.
W. The heater transfers about 240 joules of energy every second.
X. The heater will stop working if the potential difference across it is less than 240V.
Y. The resistance of the heater is 24 Ω .
Z. The supply to the heater is direct current (d.c.).
…… …...
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 9

14. Questions 6 – 9 refer to the following information.
Figure 2 shows part of the circuit diagram for a car lighting circuit.
Table 1 shows the power rating of the various lamps used in the circuit.
switch
headlights
tail lights
12 V
side lights
Figure 2
Lamp Power rating (W)
Tail light 8.0
Side light 5.0
Headlight 60
Table 1
Question 6
Explain why each set of lamps is connected in parallel.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
2 marks
The emf of the battery used in the circuit is 12 V and it has negligible internal resistance.
Question 7
Calculate the current, in A, that flows from the battery when the headlights and tail lights are both
on.
A
3 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 10

15. Question 8
State which lamp filament has the least resistance. Justify your answer.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
3 marks
The side and tail lamps are accidentally left on for 12 hours when the car is parked.
Question 9
Calculate the energy dissipated in Joule, in the lamps during this time.
J
2 marks
Questions 10 and 11 refer to the following information.
Caitlin used a simple series circuit to test and compare different types of electrical cells.
The circuit consisted of the cell being tested connected in series with an ammeter and a resistor. The
graph in Figure 7 shows the results for one cell which was left on until it failed completely. The emf
of the cell at the start of the test was 1.5 V.
Figure 3
Question 10
Calculate the total resistance, in Ω , of the circuit.
Ω 2 marks
_____________________________________________________________________
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 11

16. Question 11
Use the graph in Figure 3 to estimate the total flow of charge, in C, in the circuit during the test.
C
3 marks
_____________________________________________________________________
The manufacturer gives the following information about four different appliances as shown
in Table 2. All the appliances are designed to work from the 240V mains supply.
Appliance Current (A) Fuse required (A)
Washing machine 12 15
Television 4.0 5.0
Hairdryer 7.0 15
Table lamp 1.5 3.0
Table 2
Question 12
Choose from the alternatives, A – D, the statement that best completes the sentence.
If a 15 A fuse is used in the table lamp circuit...
A. No earth wire will be needed.
B. The table lamp will not work.
C. The table lamp will shine more brightly.
D. There could be a risk of a fire.
Justify your answer.
_________________________________________________________________________________
_________________________________________________________________________________
2 marks
_____________________________________________________________________
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 12

17. The potential difference – current characteristics for three electrical components are shown in
Figure 4.
Figure 4
Question 13
Which one of the curves labeled X,Y,Z best describes the potential difference – current
characteristics for an ohmic conductor.
Justify your choice.
_________________________________________________________________________________
_________________________________________________________________________________
3 marks
End of Area Study 2
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 13

18. SECTION B – Detailed study
Instruction for Section B
Answer all the questions in this Detailed study
Detailed study 3.1 – Astrophysics
Question 1
Describe the main features of the Big Bang theory and give evidence that supports it.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
2 marks
_____________________________________________________________________
Questions 2 and 3 refer to the following information.
The red shift of the spectrum of a galaxy can be used to calculate its velocity relative to Earth.
The wavelength of the hydrogen α line in the spectrum of the galaxy NGXC 1357 is
660.86 nm. The wavelength of the same line of the hydrogen spectrum measured in the laboratory is
656.28 nm.
Question 2
Which one of the following alternatives best explains the significance of the red shift of the
wavelength of a particular line in the hydrogen spectrum of the distant galaxy?
A. The galaxy contains more red stars than another.
B. The galaxy is receding from Earth at high velocity.
C. Wavelengths of light other than red are absorbed by the Earth’s atmosphere on entry.
D. The galaxy is approaching Earth at high velocity.
1 mark
Question 3
Calculate the velocity relative to Earth of galaxy NGC 1357.
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 14

19. Question 4
Complete Table 1 with your calculated value from Question 3 and plot a graph of the data in
Table 1 on the axes provided.
galaxy velocity (km s-1) distance (Mpc)
NGC 1357 28
NGC 1832 2000 31
NGC 7469 4470 65
NGC 5548 5270 67
Table 1
2 marks
Question 5
From your graph, determine a value for Hubble’s constant. Show your working.
km s-1 Mpc –1
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 15

20. A very recent determination of Hubble’s constant was made using information obtained from 38
galaxies. This value of Hubble’s constant was calculated as 74 km s-1 Mpc-1.
Question 6
Use this value of Hubble’s constant to determine an age, in years, for the Universe.
years
2 marks
_____________________________________________________________________
Figure 1 shows the axes of a Hertzsprung- Russell (H-R) diagram.
Absolute magnitude
- 10
+ 15
30 000 2500
temperature (K)
Figure 1
Question 7
On this H-R diagram;
A. Label with an S the current position of the Sun.
B. Label the position of star W, which is significantly hotter and brighter than the Sun.
C. Label the position of star X, which is significantly cooler and larger than the Sun.
D. Label the position of star Y, which is the same size as the Sun, but significantly cooler.
2 marks
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 16

21. Question 8
State at least two differences between elliptical and spiral galaxies.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
2 marks
Question 9
Describe the process occurring in the Sun which enables it to maintain its energy output and size.
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
_________________________________________________________________________________
2 marks
Question 10
Complete the following table by inserting the name given to the unit of distance measurement.
Name of unit Description of the unit of measurement
The average distance between the Sun and the Earth.
The distance to an object subtending 1 second of arc to the Earth’s orbit.
2 marks
The luminosity of a star is the total power radiated in watt, W.
Question 11
Which one of the following statements is correct?
A. Luminosity increases with increase in the surface temperature.
B. Luminosity increases as the surface temperature decreases.
C. Luminosity is not a function of surface temperature.
D. Luminosity is directly proportional to the surface temperature.
1 mark
End of Section B
End of examination
Lisachem Materials VCE Physics 2007 Year 11 Exam Unit 2 17

23. Suggested Solutions VCE Physics 2007 Year 11 Exam Unit 2
Question Section A – Core Area of study 1: Movement Mark
allocation
1 Use;
1 1
20 m s-1 = 30 × × 3600 km h -1
1000
1
= 72 km h -1
2 On this graph, distance traveled is found from the area under the graph. 1
Deceleration occurs between 10 s and 30 s.
Use;
1
area = × 20 × 20
2
= 200 m 1
3
The gradient of the line during this time interval is numerically equal
to the acceleration.
Use;
rise 1
acceleration=
run
30
=
10
= 3.0 m s -2 1
4 The position – time graph has a constant negative gradient. 1
The velocity is constant and negative.
Answer: Graph C 1
5 During the third second, the cyclist travels 5.0 m
The average velocity is calculated;
distance 1
v=
time
5.0
=
1.0
= 5.0 m s -1 1
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 1

24. 6 The acceleration is constant over the time interval.
Total distance = 9.0 m
Time taken = 3.0 s
Initial speed = 0
Use:
1 1
x = ut + at 2
2
1
9.0 = (0 × t ) + a × (3.0) 2
2
9.0 × 2
=a
3.02
a = 2.0 ms -2 1
7 The normal force in diagram B is less than in diagram A.
Answer: C
2
8 Kinetic energy decreases to zero, then increases again. 1
Answer: B 1
9 At the half way point, the ball will have gained half of its potential
energy and so lost half of its initial kinetic energy. i.e. E k = 5.0 J 1
Use;
1
5.0 = × 0.20 × v 2
2
10 1
v2 =
0.20
v = 7.1ms-1
10 When the jumper has come to rest, to calculate the stored energy in the
rope;
Use;
On Platform :Initially
Us = 0
Ek = 0
U g = 70 ×10 × 85 1
= 59500 J
Finally :
Us =?
Ek = 0
U g =0
Since : ∑ Ei = ∑ E f
1
then U s = 6.0 ×104 J
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 2

25. 11 Use;
U = mg∆h 1
= 70×10×85
= 59500
= 60kJ 1
12 The 10 kg mass is accelerating to the right at 2.0 m s –2.
The force causing this motion is T. 1
T = ma
= 10 × 2.0
= 20 N 1
13 The work required to compress the spring is numerically equal to the
area under the graph. 1
Use;
1
work done = × 0.080 × 25
2
= 1.0 J 1
14 U LOST = EK gained 1
1
1.0 = mv 2
2
2.0
v2 =
0.050
v = 6.3 ms -1 1
15 The increase in gravitational potential energy on rising will be
converted to kinetic energy on falling.
1 1
m × g × ∆h = × m × v 2
2
2
v = 2× g × h
= 2×10× 4.2
v = 9.2 m s -1 1
Mark
Question Area of Study 2 – Electricity allocation
1 Use Ohm’s Law;
V 1
R=
I
6.0
=
0.20 1
= 30 Ω
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 3

26. 2 The cell has an emf of 9.0 V.
Resistor R has a potential difference across it of 6.0 V.
The variable resistor must have a potential difference across it of 3.0 1
V.
Use Ohm’s Law;
V
R=
I
3.0
=
0.20
= 15 Ω 1
3 The potential difference will vary; the current will be almost the same. 2
Answer: C
4 Use;
Q = It 1
= 0.75 × 2.0 × 60
1
= 90 C
5 Use:
P = VI
P
I=
V
2400
=
240 1
= 10 A
also;
V2
P=
R
2402
R=
2400
= 24 Ω 1
Answer : V and Y
6 The two lamps are connected in parallel because if one fails, the other 1
will remain alight. If they were connected in series, then both lamps
would go out if one failed. 1
7 60 1
The current through each headlight is; = 5.0 A
12
8.0
The current through each tail light is; = 0.67 A 1
12
Total current, I, = (2 × 5.0) + (2 × 0.67)
= 11 A
1
8 The lamp with the highest power rating has the least resistance. 1
V2
Since; P = 1
R
As P increases, R decreases headlight.
1
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 4

27. 9 Use;
Energy=power × time 1
=(2 × 8.0 × 12 × 3600) + (2 × 5.0 × 12 × 3600)
1
=1.1× 106 J
10 Emf = 1.5 V
Current = 0.30 A 1
Use;
V
R=
I
1.5
=
0.30
= 5.0 Ω 1
11 The area under the curve can be broken down into triangular and
rectangular areas.
3600 × (0.30 × 1.0) + (0.5 × 0.10 × 4.0) + (0.20 × 4.0) + (0.5 × 0.20 × 1.0) 2
= 3600 × 1.4
= 5040 C 1
=5.0 × 10 C
3
12 A table lamp which carries 1.5 A of current would be a fire risk if the 1
fuse used was 15 A and there was a power surge to the appliance.
Answer: D 1
13 Graphs for Y and Z are non-linear. These indicate non-ohmic 1
character.
Ohmic conductors have linear current-voltage characteristics. 1
Answer: curve X. 1
Question Detailed Study 3.1–Astrophysics
1 The main features;
• Approximately 14 billion years ago there was a great Any two
explosion. 1
• Space/time/matter was created.
• The Universe began to expand (from a point).
The evidence;
• Distant galaxies have a red-shift in their wavelengths
(receding). any two
• This observation is in accord with Hubble’s Law. 1
• Hubble’s Law is used to ‘date’ the Universe.
• Discovery of cosmic background radiation.
2 The red shift of the spectrum of a galaxy is an indication that the
galaxy is receding from Earth. 1
Answer: B.
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 5

28. 3 Question 3
Use;
∆λ v 1
= ( −)
λ c
∆λ × c
v = ( −)
λ
(660.86 − 656.28) × 3.0 × 108
= ( −)
656.28
= (−)2100 kms -1 1
4 The graph should be a straight line of best fit passing through the 2
origin.
5 The accepted value could be; 70 ± 4 km s-1 Mpc-1 1
Gradient determination must be shown. 1
6 The age of the Universe can be found from;
1 1
T=
H0
1
= km s -1 Mpc-1
74
1 Mpc = 3.1× 1019 km
3.1× 1019
T= s
74
3.1× 1019
=
74 × 365 × 24 × 3600
= 1.33 ×1010 years
1
= 13 billion years
7
Absolute magnitude
- 10
W
X
S 2
for all
Y correct
+ 15
30000 2500
temperature (K)
8 Elliptical galaxies are usually ‘redder’ than spiral galaxies. Any
Elliptical galaxies have little gas and dust; spiral galaxies have more. two
Elliptical galaxies have a higher proportion of older stars than spiral 1
galaxies. 1
Elliptical galaxies do not have spiral arms; spiral galaxies do
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 6

29. 9 Hydrogen fusion occurs in the inner parts of the sun. This produces an
outward pressure and an expansion which tends to cool the system. 1
This causes a contraction which then initiates further hydrogen fusion.
There is a dynamic equilibrium set up which maintains temperature 1
and size.
10 Astronomical unit (AU) 1
Parsec (pc) 1
11 The temperature of a hot body is related to its luminosity. Luminosity
increases with increasing temperature. 1
Answer: A
Suggested Answers VCE Physics 2007 Year 11 Exam Unit 2 7