Recent content by tech99

The device can add inertia to the suspension travel without adding very much actual mass. If the suspension is thought of in an electrical analogue, we have inertia (inductance), springiness (capacitance) and friction (resistance). The designer will normally have only C and R to employ in his...

I thought the graticule was placed in the eyepiece so is not subject to the full magnification?

Yes, I agree with #4. An ordinary rope often has three strands, which are the bunches of fibres, and which are twisted around each other. The lay of the rope is the direction of twisting. If the strands are themselves twisted one way and are then twisted around each other the opposite way this...

If you pulse one carrier at both 5Hz and 8Hz you are, by doing this, causing a mixing process between the two pulse trains. In effect the two pulse trains are being applied to an AND gate. On the other hand, if you use two carriers, the total power received by an observer will now have three...

Yes. In the UK we are taught Fleming's Left Hand Rule for motor effect and Fleming's Right Hand Rule for Generator Effect. These rules use the conventional flow direction of electricity, which is from + to -. In the USA I think the Right Hand Rule is used for Motor Effect, and uses the electron...

I think the question was essentially why are even harmonics present with a stopped pipe.

These are my ideas on this question. A very interesting topic. The pipe is excited by a series of brief, unidirectional pulses which originate from the inner side of the lip. The pulses arise due to turbulence, giving vortices in the air stream that are shed on alternate sides from the lip, the...

The energy stored might be sufficient to cause a risk to the heart. It is allowable to touch a Van de Graaff generator but not to add a Leyden jar.

In UK schools we are not allowed to use Leyden Jars with static machines. Your experiment amounts to the same thing. Capacitor experiments can be done with low voltages.

For a resonant cavity, the magnetic and electric fields are each in the form of a standing wave. This is a wave that stands still. If the cavity has no heat losses, then no flow of overall energy is taking place and it is just an energy store. The two standing waves are displaced from each...

The only pressure required is the head of water from the water level in the top tank to the ground. Not very much. However, if a leak occurs, then a tonne of water will pour out. Why not fill the top tank from the top, with an air gap, so nothing can escape?

I have tried to read all the replies, but no one seems to have suggested Osmosis. When the clay is placed in bag of water, salts from the clay will dissolve in the water in the bag and form a solution. As this solution is more concentrated than the water in the bucket, water will pass through...

Regarding the spacing of resonance as you vary the wavelength (or frequency). Imagine a low frequency analogy. Take transmission line 5m long with a short circuits at each end. Apply some energy at frequency that can be varied from zero upwards. When the wavelength becomes 10m, corresponding to...

If you change wavelength, the resonances actually occur at fixed intervals of frequency, so are not exactly uniform wavelength intervals.

Isolated systems are used for safety on construction sites etc. A transformer is used where the secondary is not connected to earth. A problem arises, however, if the system gets very big and an accidental connection to earth occurs on one wire. Then the system is dangerous, because if someone...