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Can you expand on this?

Might have been astrophysics. Pretty sure it was in space though, had something to do with communication difficulties with satellites. Remember the Van Allen radiation belt? There are two belts. They are made up of charged particles, which got caught in the earths magnetosphere. Those charged...

Space is a pretty cool guy. Eh kills aliens and doesn't afraid of anything. p-type silicon is doped with GIII elements to produce extra positive holes, thereby increasing electrical conductivity. n-type silicon is doped with GV elements to produce extra free electrons, thereby increasing...

Dunno bro. Seems like a typo to me. I don't see why the horizontal component would come into it, plus they contradicted themselves by doing a different thing in the sample answer.

Induction Cooktops: In an induction cooktop, AC current is passed through a solenoid in order to produce a changing magnetic field. This then induces an emf in the base of a saucepan, in accordance with Lenz's law, which causes eddy currents to flow. The electrical resistance of the saucepan...

Difficult question. It takes combining your knowledge of the various topics. Do you remember learning about solar winds? That's essentially what that part two is referring to. I'm pretty sure you learn that solar winds are potentially harmful to the sensitive technology onboard the spacecrafts...

I just checked the 2009 Sample Answers. They do use vertical velocity ('the perpendicular component of the velocity'), however for some inexplicable reason they do not follow the final step and multiply by two. Parvee's right though, and, if you did it that way, you are too.

+1 At first I thought there may have been a special way to connect the slip rings to an external circuit, that I hadn't been taught, but I searched around and found zilch. It's dependant on how you connect it to an ammeter. Careful you do not confuse "current" and EMF. Where was this question...

8. If two balls achieve the same height they must have had the same Uy value (Initial vertical velocity). Furthermore, they will have the same time of flight, as time of flight is only affected by vertical velocity. This means that for them to have a different range, the must have had a...

Meisner effect is separate to induced magnetic fields. You should've done a practical at some point to prove this: Put a magnet on the material, then lower it below it's critical temperature. The magnetic will be observed to float up from the superconductor proving it is separate from induced...

When an object is moved to a higher orbit, it gains energy because work is done to move it to that new orbit and due to the Law of Conservation of Energy this cannot be destroyed. It is converted to Gravitational potential energy, which is the amount of energy the object would regain (in kinetic...

- Gravity condenses hydrogen gas into a ball. - Gravitational pressure is converted to thermal energy in the core of this ball. - When thermal pressure outwards equals gravitational pressure inward, the star lights up and begins to fuse hydrogen. Is this in the syllabus? Assess the impacts of...

Parallax is the apparent shift of an object relative to a more distant background, due to an observers motion. Annual parallax is the apparent shift of an object relative to a more distant background, due to the earths motion around the sun (i.e. using the diameter of the earths orbit as the...

Right. They move around the circuit. Cheers man. Describe the occurrence of different striation patterns in discharge tubes with explicit reference to a practical you have performed. Include diagrams.

Solar cells exploit the photoelectric effect to function. P and n-type semiconductors are placed side-by-side to form a junction. When light falls upon the n-type semiconductor, electrons are excited and move across to the p-type semiconductor. This sets up a potential difference across the...

That's impulse. Momentum = Mass * Velocity. Law of Conservation of Momentum states that momentum is a closed system (i.e. total momentum remains constant).

Your teacher may have been hinting at relativistic mass increase, where as v->c, m-> infinity. This means that the force required to accelerate to the speed of light is (F=ma) infinite, and therefore speed of light travel is impossible. However, I'm not sure that the practical impossibility of...

Wut? Neutrinos which have speeds that exceed the speed of light are discovered. Evaluate the effect this would have on the scientific community

Thompson used a modified CRT, fitted with a collimator, magnetic (hemmaholtz) coils and electric plates, to define the charge to mass ratio. First he equated the force on the cathode ray due to the magnetic and electric fields respectively, such that the beam passed through unaffected. This...

Careful. The p/n type semiconductors only gain a charge very close to the junction, in the depletion zone. The rest of them remains neutral, as far as I know. (Diagram) The Law of Conservation of Momentum states that total momentum must remain constant (i.e. P-rocket + P-exhaust = 0). As the...