Progress Examination

Physics

Progress Examination

HSC Course

2008

General Instructions

Reading time - 5 minutes Total Marks (44)

Working time - 70 minutes

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 (10)

Formulae sheets and a Periodic Table are Attempt questions 1 – 10.

provided with this question paper. Allow about 15 minutes for this section.

Answer all questions in the spaces Section B

provided. Total Marks (34)

Attempt questions 11 – 20.

Allow about 55 minutes for this part.
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

Teacher’s Use Only

Topic Analysis

Space Questions 1 to 5 …… / 5 11 to 15 …… / 17 Total …… / 22

Motors Questions 6 to 10 …… / 5 16 to 20 …… / 16 Total …… / 22

Section A Multiple Choice Questions (10 marks)

1. At which point of the roller coaster ride would the passengers experience g forces similar to those experienced by an astronaut during the first stage of launch?

A. A B. B C. C D. D

2. Which statement correctly describes the period of a satellite in low Earth orbit?

A. A satellite in low Earth orbit has a period greater than that of a geostationary orbit.

B. A satellite in low Earth orbit has a period equal to that of a geostationary orbit.

C. A satellite in low Earth orbit has a period less than that of a geostationary orbit.

D. A satellite in low Earth orbit has a period greater than or equal to that of a geostationary orbit.

3. Michelson and Morley attempted to measure the relative velocity of the Earth through the ether. They rated their experiment a failure because the expected outcome did not occur. Which of the following is the most accurate statement regarding the experiment?

A. It was thought the experiment had failed because the atmosphere interfered with the passage of light, probably causing refraction of the light.

B. It was thought that the experiment had failed because the equipment was not adequate to produce the expected outcome.

C. The experiment did not fail but actually demonstrated that the ether did not exist.

D. The experiment was performed once only and was thought to fail for undetermined reasons; the experiment was abandoned.

4. A body’s gravitational potential energy changes with its distance from a planet.

Which graph best describes the gravitational potential energy (E) of a body as a measure of its distance (d) from the planet’s surface?

5. The table gives information about the planets Earth and Uranus.

Planet / Mass (x 1024 kg) / Radius (km)
Earth / 6.0 / 6.4 x 103
Uranus / 86 / 2.4 x 104

An astronaut has a weight of 800 N on the Earth’s surface.

Using the information in the table, what is the astronaut’s weight on the surface of Uranus?

A. 800 N B. 813 N C. 786 N D. 980 N

6. An aluminium sheet was dropped and fell down through a magnetic field. In which diagram is the direction of the induced current shown by the arrowhead.

7. A wire 10 metres long, AB, cuts a magnetic field as shown as it moves from position AB to position CD in 10 seconds. The distance between A and C is 1.0 metre and the field strength is 10 Tesla.

A C

x x x x x

B D

The true statement is

A. If AB was part of a complete circuit the induced current would flow from B to A (or D to C).

B. By applying Lenz’s Law B (or D) acquires the higher electrical potential.

C. The amount of flux cut is 100 Tesla.

D. By applying Faraday’s Law the induced voltage is 100 volts.

8. A bar magnet is held suspended at rest, near a fixed coil as shown below.

When the switch is closed the bar magnet will

A. move to the right

B. move to the left

C. will remain stationary

D. It will rotate clockwise

9. 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
A. / ½ / ½
B. / ¼ / ½
C. / ¼ / x2
D. / ½ / x2

10. The following set up was used to generate electric current.

Assuming the coil starts at the horizontal, which of the following graphs best shows the current generated through a 360o rotation?

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 11 (3 marks)

A plane drops emergency food rations to the Red Cross in Central Africa. The plane is flying at 216 kmph and keeping a constant altitude above the plains below.

The person dropping the rations measures the time of fall to be 15 seconds to impact.

(a) Calculate the final velocity of the food rations just before impact. 2

...... …..

(b) Calculate the plane’s altitude. 1

...... …..

Question 12 (4 marks)

(a) An astronaut repairing a satellite in orbit lets go of his spanner. Describe the spanner’s 1

subsequent motion after leaving the astronaut’s hand.

…………………………………………………………………………………………………………

(b) The spanner has a rest length of 30 cm and a rest mass of 5 kg. If the speed of the spanner was later determined to be 0.3c, determine the length and mass measured by a stationary observer on Earth. 3

length calculation …………………………………………………………………………………

…………………………………………………………………………………………………………

mass calculation …………………………………………………………………………………

…………………………………………………………………………………………………………

Question 13 (2 marks)

A body is discovered orbiting the Sun at a distance equal to 16 times the distance of the Earth from the Sun. Calculate (in Earth years) the time it takes the body to complete one orbit of the Sun. 2

…………………………………………………………………………………………………………

Question 14 (4 marks)

A satellite is orbiting the Earth in a more or less circular path, completing each orbit in 90 minutes.

(a) Describe fully the net force that is acting on the satellite. 2

………………………………………………………………………………………………

(b) Using the known data for the Earth, calculate the average distance of the satellite above the Earth’s surface. (Radius of the Earth = 6.33 x 106 m) 2

………………………………………………………………………………………………

Question 15 (4 marks)

A 1 tonne satellite has been launched from Earth and sometime later the potential energy of the satellite was determined to be -3.97 J.

(a) Determine the distance of the satellite from the centre of the Earth at this point. 2

……………………………………………………………………………………………………………

(b) The escape velocity of the Earth can be determined using, in part, the gravitational potential energy formula. Calculate the escape velocity for the Earth. 2

……………………………………………………………………………………………………………

Question 16 (2 marks)

A wire carrying a current of 2.0A is placed in an external magnetic field of 1.0 T. The wire is perpendicular to the magnetic field.

(a) If the wire experiences a force of 4.0 N, calculate the length of the wire. 1

………………………………………………………………………………………………………

(b) In which direction does the force act? 1

………………………………………………………………………………………………………

Question 17 (5 marks)

When a small metal cylinder is dropped into one end of the copper tube shown below, it falls freely under the action of gravity.

Yet a small magnet of identical dimensions takes much longer to fall through the tube.

(a) Explain this observation. 3

...... …..

(b) Outline how a similar phenomenon is used in certain braking mechanisms. 2

...... …..

Question 18 (4 marks)

(a) Two coils of wire are situated near to each other as shown. Coil A is connected in series with a large source of alternating current, while coil B has a small lamp in a series connection.

Explain why the lamp connected to coil B glows when circuit A is switched on. 2

……………………………………………………………………………………………………………

A piece of soft iron in the shape of a rod is passed through the both coil A and coil B. The following observations were made during the experiment:

· the rod became warmer

· (the lamp glow became brighter

(b) Explain the increase in temperature in the rod. 1

……………………………………………………………………………………………………………

Question 19 (4 marks)

(a) State the purpose of transformers in electrical circuits. 1

…………………………………………………………………………………………………………

(b) Discuss the impact of the development of transformers on society. 3

…………………………………………………………………………………………………………

Question 20 (2 marks)

Explain why, as an electric motor begins from rest, a back emf will build in the coil. 2

…………………………………………………………………………………………………………

Physics HSC Progress Exam 2008 Page 11 : Candidate Number: ......