Download HSC Progress Examination 2009

Physics
Progress Examination
HSC Course
2009
General Instructions
Reading time -
5 minutes
Working time -
70 minutes
Total Marks (50)
Board-approved calculators may be used.
This paper has two sections:
Write using blue or black pen.
Section A
Draw diagrams using pencil.
Total marks (12)
Formulae sheets and a Periodic Table are
Attempt questions 1 – 12.
provided with this question paper.
Allow about 18 minutes for this section.
Answer all questions in the spaces
Section B
provided.
Total Marks (38)
Attempt questions 11 – 22.
Allow about 52 minutes for this part.
Physics HSC Progress Exam 2009 Page 1 : Candidate Number: .....................................................
Section A
Multiple Choice Answers
For each question place a cross (X) in the column which matches your choice.
Question
A
B
C
D
1
2
3
4
5
6
7
8
9
10
11
12
Teacher’s Use Only
Topic Analysis
Space
Motors
Questions 1 to 3
…… / 3
13 to 15
…… / 10
Questions 4 to 6
…… / 3
16 to 18
…… / 10
Questions 7 to 9
…… / 3
19 to 20
…… / 8
Questions 10 to 12
…… / 3
21 to 22
…… / 10
Total Mark
…… / 50
Total …… / 26
Total …… / 24
Task Ranking ...... / 16
Physics HSC Progress Exam 2009 Page 2 : Candidate Number: .....................................................
Section A
1.
Multiple Choice Questions (10 marks)
The force on an object due to a gravitational field is known as its
A. mass
B. gravitational potential energy
C. weight
D. acceleration
2.
Astronauts are more easily able to cope with an application of g-forces which results in the eyeballs
undergoing relative motion towards the body rather than away from it. Which of the following
combination of astronaut positions are most desirable to achieve this effect?
A. Astronaut facing in the direction of motion during launch and re-entry.
B. Astronaut facing opposite to the direction of motion during launch and re-entry.
C. Astronaut facing in the direction of motion during launch and facing opposite to the direction of
motion during re-entry.
D. Astronaut facing opposite to the direction of motion during launch and facing in the direction of
motion during re-entry.
3.
This question refers to the following diagram.
The projectile is initially fired at a speed of 35 m/s at 30o to the horizontal.
At the top of the trajectory the velocity and acceleration of the ball (respectively) would be
A. 30 m/s and -9.8 m/s2
B. 30 m/s and 9.8 m/s2
C. 35 m/s and -9.8 m/s2
D. 35 m/s and 9.8 m/s2
Physics HSC Progress Exam 2009 Page 3 : Candidate Number: .....................................................
4.
Which of the following statements is NOT consistent with Einstein’s postulates in his theory of special
relativity?
A. The light from the headlights of a rapidly reversing spacecraft will travel at the speed of light.
B. The laws of physics have the same form inside a spacecraft travelling at half the speed of light as
they do inside a stationary spacecraft.
C. The light from the headlights of a spacecraft travelling at half the speed of light is no faster than
the light from the headlight of a stationary spacecraft.
D. The laws of physics have the same form inside an accelerating spacecraft as they do inside a
stationary spacecraft.
5.
Which of the following statements is a valid conclusion which may be drawn from the MichelsonMorley experiment?
A.
The aether does not exist.
B.
There is an aether, but the equipment used by Mickelson-Morley was not sensitive enough to
detect it.
6.
C.
They have achieved a null result.
D.
No conclusion can be made about the existence of the aether.
An object in an orbiting spacecraft appears “weightless”. Which choice correctly identifies the net
force acting on the object?
A.
zero net force
B.
gravitational force
C.
inertial force forwards
D.
centrifugal force
Physics HSC Progress Exam 2009 Page 4 : Candidate Number: .....................................................
7.
The turning moment of a force is known as the
A. magnetic field.
B. motor effect.
C. torque.
D. back emf.
8.
In the experiment pictured below the force between the two parallel conductors is determined by
passing a known current through the conductors.
Choose the action which will most help to ensure that the experiment is valid.
A. Repeating it several times so that you can declare a result average over several observations
B.
making allowance for the back emf produced.
C.
Ensuring that the measuring instruments are properly calibrated before you start.
D. Ensuring that all readings and measurements are accurately made and recorded.
9.
A bar magnet is moved quickly into a coil of wire connected to an ammeter. A current of 8 A is
produced. If this experiment is repeated using two bar magnets identical to the first one (taped
together, side by side) and a different wire coil containing twice as many turns as the first one, the
expected current would be
A. 4 A
B. 8 A
C. 16 A
D. 32 A
Physics HSC Progress Exam 2009 Page 5 : Candidate Number: .....................................................
10. High voltages are used in distributing electricity over large distances. Which set of values in the
following table summarises the effect on power loss and current if the voltage is doubled?
Power Loss Current
11.
A.
½
½
B.
¼
½
C.
¼
x2
D.
½
x2
A student made the sketch below of an experiment demonstrated by his teacher. It appears to show a
metal ring suspended on a long soft iron rod core of an electromagnet.
Select the statement which is the best explanation of the record made by the student.
A.
B.
C.
D.
12.
The student’s diagram has to be incorrect as aluminium rings cannot stay suspended.
The aluminium ring is magnetic and therefore repelled by the field of the electromagnet.
The aluminium ring is a superconductor and is demonstrating magnetic levitation.
There are eddy currents set up in the aluminium ring and their magnetic field results in repulsion
by the magnetic field of the electromagnet.
A wire ring is placed in a magnetic field and the magnetic field within the ring changes as shown.
As the magnetic field is changed:
A. a clockwise current is generated by a change in flux.
B. an anticlockwise current is generated by a change in flux.
C. there is no current produced by the change in magnetic field strength.
D. an alternating current is produced by a change in magnetic field strength.
Physics HSC Progress Exam 2009 Page 6 : Candidate Number: .....................................................
Section B
Short Answer Questions
(34 marks)
Answer each question or part of a question in the space provided.
Note that marks vary from question to question.
Question 13 (4 marks)
(a)
Discuss the effect of the Earth’s orbital and rotational motion on the launch of a rocket.
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(b)
Given the radius of the Earth is 6400 km, the rocket places a satellite into a stable orbit of altitude
6500 km. Calculate the period of the satellite.
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Physics HSC Progress Exam 2009 Page 7 : Candidate Number: .....................................................
Question 14 (3 marks)
A satellite has a mass of 250 kg and orbits the Earth at an altitude of 3000 km. The Earth’s equatorial
diameter is 12 756 km.
(a)
Determine its orbital speed.
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(b)
Compare the orbital speed of a 500 kg satellite in an identical orbit.
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Question 15 (3 marks)
Three planets orbiting a distant star have the following properties:
Property
Planet X Planet Y
Planet Z
Diameter (km)
4000
6000
16000
Mass (kg)
2 x 1023
8 x 1023
1.2 x 1024
Orbital Period
200
300
800
200
1.50
1.67
(days)
Rotational Period
(days)
Predict which planet would have the greatest gravitational acceleration at it surface. Justify your answer.
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Physics HSC Progress Exam 2009 Page 8 : Candidate Number: .....................................................
Question 16 (3 marks)
Explain the idea of the relativity of simultaneity, giving an example to support your answer.
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Question 17 (5 marks)
(a)
Explain what is meant by the term “equivalence between mass and energy”.
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(b)
Most celestial objects outside our Solar System are too distant to reach at current maximum speeds.
Discuss the prospect of near-light speed space travel to such destinations with reference to relativistic
changes in mass, time and length.
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Physics HSC Progress Exam 2009 Page 9 : Candidate Number: .....................................................
Question 18 (2 marks)
Einstein’s Theory of Special Relativity made predictions about time, length and mass measurements for
objects travelling at speeds approaching the speed of light.
Calculate the mass of a proton when it is travelling at 75% the speed of light.
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Physics HSC Progress Exam 2009 Page 10 : Candidate Number: .....................................................
Question 19 (4 marks)
Below is a photograph of a hand-operated AC / DC generator.
(a)
Identify the function of the split-ring commutator in this generator.
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(b)
Compare a DC generator to a DC motor.
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Physics HSC Progress Exam 2009 Page 11 : Candidate Number: .....................................................
Question 20 (4 marks)
The following graph (for a simple DC motor) shows the variation of torque as the angle between the plane
of the coil and the uniform magnetic field changes.
(a)
A current of 600 mA is travelling through the windings when the coil is parallel to the magnetic field.
The coil consists of 200 turns of wire and has an area of 1.5 x 10-3 m2. Use this information and the
graph above to calculate the magnetic field strength.
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(b)
Sketch the variation of torque with angle if all other variables are kept the same as in part (a) and
magnetic field strength is halved.
Physics HSC Progress Exam 2009 Page 12 : Candidate Number: .....................................................
Question 21 (4 marks)
“If someday they say of me that in my work I have contributed something to the welfare and happiness of
my fellow man, I shall be satisfied.” George Westinghouse
Assess the impact on the environment of the AC generator to determine if George Westinghouse would be
satisfied.
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Physics HSC Progress Exam 2009 Page 13 : Candidate Number: .....................................................
Question 22 (6 marks)
In the picture below, the transformer has 50 turns in its primary coil and 15 in the secondary coil.
(a)
If the initial primary voltage is 240V, calculate the output voltage of this transformer.
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(b)
Explain why it is necessary to transmit electricity at high voltages.
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(c)
Outline where and how a transformer similar to the one above could be used to assist in the
transmission of high voltages (approximately 35 kV) to a home requiring only a 240 V supply.
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(d)
Identify ONE other location in which this type of transformer is commonly used within a household.
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Physics HSC Progress Exam 2009 Page 14 : Candidate Number: .....................................................