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@chilli 412 Sorry, that design won't work. :p There are no hangers (connections) between the arch and the deck. You fail. Try one of the free online truss calculators, such as https://labs.degreetutors.com/structureworks/truss2d

The diagram is examining your understanding of the motor effect. In particular, can you analyse problems involving a single current-carrying loop immersed in a uniform magnetic field. The axis PQ represents the axis of a crude motor. We sometimes refer to the orientation of the loop using...

Ideally, you should include two buffers that span the region you are interested in. pH4 is outside the region of interest, but it is better than nothing. So were you able to adjust the slope on your pH meter so that you could reliably measure pH 4? The expected Ka for ethanoic acid at 25 C is...

The first question that needs to be asked is, "Did you calibrate your pH probe in the region you expected to measure?" The electrode potential of the glass pH electrode drifts considerably over weeks. It needs to be calibrated daily. You should use buffer solutions in the range pH3 to check its...

Yes, it is part of the syllabus. It is Module 8, Nature of Light, Origins of the Elements. "Investigate the evidence that led to the discovery of the expansion of the Universe by Hubble". Leavitt came before Hubble. Hubble could not have made his discovery without a way to calibrate the...

I will assume that you are talking about an Ohmic conductor, and not a semiconductor or something else. The simplest first-hand method uses Ohm's Law. Apply a measured potential difference across a component, while measuring the current flowing through the component. The ratio of V divided by I...

The statement seems pretty clear to me. Society must focus on reducing waste, or increasing the efficiency of utilising electrical energy. It is not about ethics, this is about economics. This is a hot topic at the moment, with the price of electrical energy expected to double in the next year...

Nah, that can't be right. Strontium hydroxide is not that soluble. I calculated a value of 3.09 x 10^-4 which seems to agree with the literature value. Have a look at my working (attached).

You definitely should not be marked down for taking more space to give your answer. However, in my experience, the longer the answer, the greater the chance that a student will write something that is contradictory. As soon as a marker sees contradiction, the marker is likely to believe that the...

Yes, pressure will increase. There are three factors at play here. (1) Gay-Lussac's Law. If the container has a fixed volume 1 Litre, even if there is no change to the molar ratio of gases, the pressure must increase in accordance with Gay-Lussac's Law. (2) The shift of equilibrium caused by the...

This looks like a mistake (that's a very suspicious looking 45 degrees). Recall that the expression for the positions of intensity maxima says: n*lambda=d* sin(theta). Look closely at the diagram and you will notice that the paths converge, not at a maximum, but at a minimum. Therefore n = 1.5...

@fuzi I invite you to do the calculations, use either the method of joints or the method of sections, and I think you will find that my statement is correct. The top members will be in compression and the bottom members will be in tension. If this was not the case, then the whole structure...

Have a look at the Second Moment of Area of a beam, "I". The Second Moment of Area is a measure of the stiffness of a beam. Maximum stress in a beam is inversely proportional to "I". If you make "I" as large as possible, the stress will be minimised, and it is stress that causes failure. The...

All the options use neutralisation of a monoprotic acid by sodium hydroxide. All the reactions form one mole of water per mole of acid and base, therefore the enthalpy change for neutralisation is -57 kJ/mol of water formed, so their molar enthalpy change is almost identical. However, the heat...

For a full discussion of Collision Theory and equilibrium, see this previous post: https://www.boredofstudies.org/threads/equilibrium-constant-and-temperature.401433/

Yes! Absolutely. That is why the front cover of the examination paper says, "Draw diagrams using pencil." (and I would add, please use a ruler 👍)

Sort answer - Yes, you do. You may be asked questions targetting Module 5, such as 2021 HSC Chemistry Q.33 that use the Gibbs Free energy change. In Year 11 you were introduced to the Gibbs Free Energy change as the driving force for chemical change. In Year 12, you were shown that a system that...

A very-well designed AC transformer can be 98 percent efficient. There are three main ways that energy is wasted in AC transformers. (1) electrical resistance in the conductors. (2) magnetic hysteresis in the core material. (3) eddy currents in the magnetic core material. This wasted energy...

Without seeing the notification of the assessment task, I'm guessing that the difference comes down to secondary data versus first-hand data. The HSC Syllabus says that students need to develop both kinds of skills at Stage 6. To analyse secondary sources, you need to identify reliable sources...

This topic is never explained properly; I sympathise with your doubts and confusion. Let's start with temperature. What is temperature? Temperature is a measure of the average kinetic energy of particles. The Maxwell-Boltzmann distribution function describes how the kinetic energy of particles...