Search results

  1. P

    HSC 2015 MX2 Marathon (archive)

    Re: HSC 2015 4U Marathon I had the same method as porcupine for the 2nd part. Mind sharing your approach?
  2. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Next Question: The Michelson-Morley experiment attempted to measure the relative velocity of the Earth through the aether. a) Explain why the Earth was believed to be travelling through the aether (2 marks) b) Evaluate the effect that the result of the M-M...
  3. P

    HSC 2015 MX1 Marathon (archive)

    Re: HSC 2015 3U Marathon i) Using tan(a-b) = tana - tanb / 1+tanatanb, show that 1+tannθtan(n+1)θ = cotθ(tan(n+1)θ-tannθ) ii) Prove by mathematical induction that tanθtan2θ + tan2θtan3θ + ... + tannθtan(n+1)θ = -(n+1) + cotθtan(n+1)θ for all integers n>=1
  4. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive OK! Newton's first law (inertia) states that an object will continue to move at constant velocity unless acted upon by an external force. Based on this, Apollo 13 should continue on its path towards earth even if no external force existed. Newton' developed...
  5. P

    Parametrics gradients

    Just say if I have a line with collinear points PMQ. If I were to calculate the gradient of the end points P and Q, is it viable to use the gradient of PM (or QM) instead? (if so, do I need to state it in my proof)
  6. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive after considering the markers notes haha I wonder in what way Newton's 2nd law can be applied?
  7. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Here's my attempt: Lovell's statement refers to Newton's laws of motion which are responsible for their return back to Earth. Newton's first law of inertia states that an object will continue to move unless acted upon by an external force. As the spacecraft...
  8. P

    HSC 2015 MX2 Marathon (archive)

    Re: HSC 2015 4U Marathon Wasn't really sure what to do because i've only seen arg(z-2) - arg (z+2) = +-pi
  9. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive next question: http://imgur.com/yUVJX3R (I like this one because of the diagram) a) determine the maximum height reached above the ground by the projectile (1 mark) b) does the projectile have the correct range to hit the wall? justify your answer using...
  10. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive In your response you should refer to the forces acting on the spacecraft. What is the main force acting on it to maintain a stable orbit? What are the forces it experiences during re-entry, and how does that effect the motion of the spacecraft? (Taken from...
  11. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Not sure if the current question has been answered, but here's another one: Parts of a space mission involve a spacecraft spending time in geostationary orbit, and then returning safely to Earth. Analyse the forces acting on this spacecraft during these parts of...
  12. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Yeah, I was having the same problem. I tried multiple approaches but they ended up contradicting each other
  13. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Any hints please?
  14. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive Let's restart this marathon: An object is stationary in space and located at a distance 10 000 km from the centre of a certain planet. It is found that 1.0 MJ of work needs to be done to move the object to a stationary point 20 000 km from the centre of the...
  15. P

    projectile motion

    If you haven't worked them out by now http://imgur.com/DHzdaTA
  16. P

    HSC 2015 MX2 Marathon (archive)

    Re: HSC 2015 4U Marathon Write in simplest form: (sinθ - icosθ)^-8
  17. P

    HSC 2015 MX2 Marathon (archive)

    Re: HSC 2015 4U Marathon Let P(z) = iz^2 + (ia-1)z + (i-b) For z = 1 to be a root, P(1) = 0 ∴ P(1) = i + ia-1 + i-b = 0 i(2+a) - (1+b) = 0 ∴ a = -2, b = -1
  18. P

    Gpe question

    Explain why the energy needed to place a satellite in orbit is greater than the work required to lift the satellite to the correct height of this orbit. In other terms,why does it take more energy to put a satellite into orbit at x km altitude than it does just to lift it up to x km?
  19. P

    HSC Physics Marathon 2013-2015 Archive

    re: HSC Physics Marathon Archive For person A, it would take 25/0.8 = 31.25 years For person B, it would take 25/0.6 = 41.67 years But time also dilates so... using tv = t0 / √(1-v^2/c^2) For A, 31.25√ (1-(0.8)^2 = 18.75 years For B, 41.67√ (1-(0.6)^2 = 33 years So B will be older...
Top