The Hubble Space Station

Physics

Theme:

“The Hubble Space Station”

Cast of Characters

Olivia – main character

Alison – manager of Hubble

Mel – evil driver of car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior)

Penny – evil

Sophie – evil

Anna – stone

General Instructions

· Reading time – 5.0 ± 0.1 minutes

· Working time – 2.00001 hours

· Board-approved calculators may be used

· Write using blue or black pen

· Draw diagrams using pencil

A Data Sheet and Formulae Sheet are provided at the back of this paper.
Part A

Total marks (15)

Allow about 25 minutes for this part

Use the multiple choice answer sheet.

Select the alternative A, B, C or D that best answers the question. Fill in the response oval completely.

Sample 2 + 4 = (A) 2 (B) 6 (C) 8 (D) 9

A B C D

If you think you have made a mistake, put a cross through the incorrect answer and fill in the new answer.

A B C D

If you change your mind and have crossed out what you consider to be the correct answer, then indicate this by writing the word correct and drawing an arrow as follows:

correct

A B C D

Outcomes Assessed

P1 evaluates how major advances in scientific understanding and technology have changed the direction or nature of scientific thinking

P2 analyses the ways in which models, theories and laws in physics have been tested and validated

P3 assesses the impact of particular advances in physics on the development of technologies

P5 identifies possible future directions of physics research

P6 explains events in terms of Newton’s Laws, Law of Conservation of Momentum and relativity

P7 explains the effect of energy transfers and transformation

P8 analyses wave interactions and explains the effects of those interactions

P9 explains the effects of electric, magnetic and gravitational fields

P10 describes the nature of electromagnetic radiation and matter in terms of the particles

P11 justifies the appropriateness of a particular investigation plan

P12 evaluates ways in which accuracy and reliability could be improved in investigations

P14 assesses the validity of conclusions from gathered data and information

Part A

Total marks (15)

Attempt Questions 1 – 15

Allow about 25 minutes for this part

Mel, the evil driver of the evil twins Penny and Sophie, was driving in their car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior) listening to EVL98.1 MHz

1. What is the velocity of the wave carrying the FM signal?

(a) 98.1 m/s

(b) 330 m/s

(d) 3 X 108 m/s

All of a sudden, an elephant fell out of the last exam and crashed into some bushes next to the road. It was really mad. It charged at the car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior).

2. If the elephant (mass = 3000 kg) charging at 4 m/s collided head on with the car (mass=1500 kg, including occupants) travelling at 2 m/s, and the elephant rebounded at 1 m/s, then the rebound speed of the car would be

(a) 1 m/s

(b) 2 m/s

(d) 4 m/s

Both the elephant and car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior) fell over a cliff and down a slope towards a spacecraft launch site.

3. If the elephant’s initial speed down the slope was 1 m/s and its final speed was 12 m/s at the end of the 100 m slope, then its acceleration down the slope was

(a) 0.72 m/s2

(b) 6.2 m/s2

(d) 143 m/s2

The elephant and car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior) slid into the open doors of a cargo delivery module for the space shuttle on the launch pad. The doors promptly closed shut. Olivia, the captain, was making final rounds of the area and supervised the loading of the cargo module into the spacecraft. She noticed that the cargo module had become magnetised for some reason…

4. The cargo module had a magnetic field that looked identical to one created in a current-carrying wire. The magnetic field looks like

(a) (c)

(b) (d)

Olivia was satisfied that this magnetic field would not affect the launch and so activated the switch that loaded the cargo module into the space shuttle. A schematic diagram of the switch looks like this:

switch

100V

5 kW 5 kW

5. What is the current through the switch when it is closed?

(a) 0.01A

(b) 0.04A

(d) 4000A

Meanwhile in the cargo bay a dazed Mel, Penny, Sophie and elephant were slowly waking up after the fall. Suddenly there was a very loud roar followed by a 30 second period were their weight was increased exactly three times normal Earth gravity.

6. If the space shuttle had started from a stationary point, then its speed at the end of the 30 seconds is

(a) 10 m/s

(b) 294 m/s

(d) 1289 m/s

7. After being pinned to the floor for 30 seconds, Penny reached into her pocket and tried to use her mobile phone to call her evil headquarters. All she got was static. This is because

(a) the phone was not in direct line of sight with a base station.

(b) the phone could not withstand the acceleration.

(d) the signal was superimposed on a carrier wave produced by the spaceship’s engine.

The space shuttle ascended through the atmosphere and at an altitude of 500 km passed through the first van Allen radiation belt. This is a region of highly charged plasma surrounding the Earth’s equator that is created when the Sun’s solar wind hits the Earth’s magnetic field (we’ll learn more about this after the exam…). Olivia could feel the strain of the engines as sparks danced across her instrument panel.

8. Olivia (and everyone in the cargo bay) did not get electrocuted as they passed through the radiation belt because

(a) she was (electrically) grounded.

(b) the electrical discharges went across the hull of the spaceship.

(d) the magnetic field of the radiation belt penetrated the hull of the spaceship.

Once passed the van Allen radiation belt, their destination was in sight: the Hubble space station, also known as Thunderbird 5. Virgil Alison was manager of the station and co-ordinated a group called International Rescue from this place.

9. Olivia established a modulated laser communication link with the space station. She used a carrier frequency of 103 THz. This type of communication is

(a) FM using a microwave spectrum.

(b) AM using a microwave spectrum.

(d) AM using a terahertz spectrum.

10. Olivia was now moving the space shuttle to dock with the Hubble space station (Thunderbird 5). To cushion the impact, the space shuttle and space station should have

(a) crumple zones.

(b) low speed zones.

(d) wombat crossings.

Meanwhile, floating through space was an unassuming rock. Little did the people on the space station that this rock was actually Anna, a rock alien from the planet Wu. Anna collided with the Hubble space station and stuck to it using an electrostatic force.

11. If Anna collided with the space station with a force of 5MN and has a charge of 40C, then the minimum electric field she needs to generate to stick to the space station is

(a) 0.125 V/m.

(b) 12.5 V/m.

(d) 125 kV/m.

12. Mel, Penny and a startled elephant looked out of the cargo bay windows and were surprised to see that the Earth was not spherical after all, but was flat, supported on four really big elephants, who in turn were standing on a gigantic turtle. Which group of peoples were right, after all?

(a) Greeks.

(b) Indians.

(d) Babylonians.

Penny exclaimed: “What a conspiracy! We’ve been lied to all these years! The Earth is not a sphere – we need to tell everyone, and then use this knowledge to take over the Earth! Mel, ready the car (Mercedes, SL500, silver with blue tinge, V8 engine, leather interior), we’re getting out of here.”.

13. The best way for Penny to communicate with her minions on Earth and all other Earthlings to send a clear message around the world is

(a) Low frequency AM.

(b) High frequency AM.

(d) High frequency FM.

The elephant had already started breaking down the cargo bay doors. Fortunately the cargo module had already been loaded into the space station by this time. Anna the rock alien had also slipped into the space station through an open airlock. She was not used to this yellow Sun, her world was lit by a blue supergiant.

14. Both the yellow Sun and the blue supergiant are their colours due to

(a) the proton-proton chain.

(b) helium flash.

(d) black body radiation.

15. Anna feeds on neutrinos. While not the easiest of meals to obtain, there are plenty around. For this, Anna is thankful of the

(a) the proton-proton chain.

(b) helium flash.

(d) black body radiation.

Part B

Total marks (45)

Attempt Questions 16 – 24

Allow about 75 minutes for this part

Answer Questions 16 – 20 in this answer booklet.

Show all relevant working in questions involving calculations.

The Plot.

Sophie had a brilliant idea “What if we take over Thunderbird 5/the Hubble space station and control the world from here?”. Mel said “OK, but we’ll have to walk from here. The elephant is jammed against the car so tightly that neither can get through this hole into the space station, and besides, the corridors in this space station are too narrow for the car anyway.”

Question 16 (6 marks) Marks

Penny, Sophie and Mel started walking along the corridor at a pace of 3 m/s. The walls of the corridor were mirrored and they seem to be walking in a very gentle curve. If the mass of each evil person is 50 kg,

(a) Calculate the combined momentum of the group (3 people) 1

(b) The group walked straight into a glass door they couldn’t see. If the door shattered on impact, discuss the collision in terms of force, impulse and energy. 3

(c) Explain the difference between mass and weight and how the weight of the evil doers is different to their weight on Earth 2

Question 17 (6 marks) Marks

The mirrors in the corridors actually acts as a giant optical fibre for communication around the Hubble space station.

(a) Outline how total internal reflection is used in optical fibres. 3

(b) The refractive index from air to the type of glass in the walls of the corridor is 1.5. Calculate the critical angle for a light beam in the corridor. 3

Question 18 (7 marks) Marks

Olivia, meanwhile, had exited the shuttle and made her way to the control centre of the Hubble space station where she met Alison, the manager of the station. Anna rolled into the room, as rocks do, and telepathically talked to Olivia and Alison, who were a bit shocked at the idea of talking to a rock. Anna was upset that she couldn’t get home to planet Wu and needed help. Olivia suggested that they had an experimental matter-antimatter deep space probe ready for launch that might do the trick…

If the space probe relied on a proton-antiproton annihilation to power it

(a) State an equation showing this annihilation. 1

(b) Calculate how much energy is released in a proton-antiproton annihilation 2

Alison displayed the schematics of the deep space probe and found a way to squeeze Anna in. She could remove the attack laser from the deep space probe (it had been designed by the military). A simplified version of the space probe’s circuitry is outlined below

10 kW 5 MW

250 MV

5 MW 5 MW

10 MW

(d) Calculate the current through the sensors AFTER the removal of the laser. 2

Question 19 (6 marks) Marks

As Alison set about removing the laser from the space probe, Penny, Sophie and Mel had arrived at the control centre. To put their evil plan into action, they distracted everyone by stopping the space station from spinning.

(a) Explain how the spinning of the space station produces an artificial gravity 2

(b) If the radius of the space station is 60 metres, calculate the linear speed needed to produce gravity equivalent to 0.8g 2

Question 20 (6 marks) Marks

The space station jolted as it suddenly stopped spinning. All communication with Earth was interrupted. Unfortunately the Hubble space station at this time co-ordinates all Global Positioning Satellite information.

(a) Discuss some of the underlying physical principles used in the Global Positioning System. 3

(b) If a typical GPS satellite runs at 2 kV and 300A,

(i) Calculate its power output. 1

(ii) Calculate its effective resistance. 1

(iii) Calculate how much energy it uses each minute. 1

Question 21 (7 marks) Marks

Penny and Sophie tried to wrestle Alison and Olivia to the ground, which is difficult to do in a zero-gravity environment. Mel just watched (drivers aren’t paid to do the evil dirty work). Anna, whose life as a rock alien is always in zero-g, was a lot more agile and managed to push the evil trio out of the control room and into the deep space probe launch bay where. Anna pushed the evil doers using a series of electric and magnetic fields right into the space probe along with herself.

(a) Explain one application of magnetic fields in household appliances. 3

(b) Since Anna is a highly electric life form, her touch can be lethal to humans. Discuss the dangers of an electric shock from both a 240 volt AC source and various DC voltages, from appliances and alien life forms, on the muscles of the bodies of the evil doers 4