Recent content by romesh

  1. R

    Escape Velocity Question!!!

    Actually I think that Kerbal Space Program would be a great teaching aid for high school space/orbital physics, because by dropping some of the realism of Orbiter it really gets to the important concepts
  2. R

    The Student's Guide to HSC Physics

    I did ask the mods to sticky it, but they said they had a backlog and they'd get to it, and next thing I knew the request was closed...not sure what happened
  3. R

    Problem help

    There is enough information :) I'm not 100% sure about how you would go about solving it using HSC physics equations. The mathematics way of doing this problem is: Suppose that the stone is dropped at time t=0. Let the balloon velocity be v_0. The stone starts out at a height x=10*v_0 (the...
  4. R

    Earth travelling through space - we can/cannot feel it?

    Maybe they don't teach this clearly enough in HSC, but when it comes to 'feeling' force, you don't feel gravity. The reason, I suppose, is that you don't feel any force along a free-fall trajectory (neglecting friction). The reason you 'feel' weight on Earth is because you are *not* in free...
  5. R

    Centripetal force (help....)

    If it is a frictionless road, then friction between the internal parts of the car won't matter. You can see this by imagining the car sliding on the frictionless road without the wheels turning or any other parts within the car moving- it will keep sliding until an external force acts on it. For...
  6. R

    The Student's Guide to HSC Physics

    Hi everyone, thanks for all your positive comments :) Now that it is time for trials, if you haven't already had a look at the guide I would highly recommend taking a few minutes to click on the link. Some schools have been using my guide as a teaching aid, but they were really written with...
  7. R

    Magnetic Flux Density

    I don't find this explanation plausible. You are correct that B corresponds to the 'magnetic flux density'. However, phi depends on A, because phi is measuring the amount of magnetic flux going through the loop. B is a property of the external field, and isn't changing. When you change the area...
  8. R

    Multiple Choice Help

    These are interesting questions. Q1. I don't think this is a very good question. Why? Because normal stars *do* move. This is why you can take long-exposure photos like this - it is just a result of the Earth rotating. However, the whole...
  9. R

    WTF??? adv/disadv for these?

    Yeah, I think the problem is that they come up with the verbs planning special definitions for them, but then write some of the dotpoints in a more normal colloquial sense- like these particular dotpoints make sense just reading them as plain sentences (discuss = 'talk about')
  10. R

    WTF??? adv/disadv for these?

    This comes up time and time again- not all 'discuss' dotpoints need advantages and disadvantages. Some of them (like these ones) just require a detailed explanation. Just use common sense to decide which dotpoints fit into this category. Exactly the same deal as your other thread about "Assess...
  11. R

    Disadvantage on Einstein's work on quantum theory.

    I don't think this needs disadvantages, they are looking more for your understanding of how Einstein's work shaped future developments in quantum theory. So you would need to explain in what way future development utilized Einstein's results and thus evaluate the consequence of Einstein's...
  12. R

    Simple g Force questions

    This is a strange question- I don't understand why the resulting force acting on the astronaut is different to the upwards force exerted by the chair. Why? Because when the rocket is sitting on the ground, the chair is already exerting an upwards force of mg (reaction force of gravity). So the...
  13. R

    in simple words plz explain

    You've just listed the main differences. Btw silicon solid state devices *are* the convention today, you should probably refer to valves etc. as thermionic devices. Compared to thermionic devices, silicon devices have - Better heat dissipation (less waste heat) - Stronger - Longer expected...
  14. R

    Why is classical physics = ultraviolet catastrophe

    Also, you have to remember that the emission of radiation constitutes energy loss from the heated object. That is, if you heat an object so that it is glowing *and* at a constant temperature, then the amount of energy you are putting in to keep it hot must be same as the amount of energy it is...
  15. R

    What are some disadvantages on Einstein's development of quantum theory?

    You need to think carefully about the key verb in this dotpoint- in this case, 'assess'. You've correctly identified that this is similar to a 'discuss' dotpoint, except you need to make a conclusion at the end. However, it is important to remember that not all 'discuss' dotpoints have arguments...