Russell McMahon
• Member for 6 years, 11 months
• Last seen this week
• Auckland, New Zealand

If this was a quiz show and you had one guess, the safest offering may be 'The suspension system in a vintage Scorpion snowmobile", BUT "Para rail" and "pararail" are 'made up' words usually used as ...

Fill Factor is important for PV (photovoltaic) cell and panel designers but of less direct importance to users. What is usually more important are the practical parameters which result from a given ...

As well as mechanical properties and lack of conductivity you need a means of creating the charge to be transferred. The following table gives the relative amount and the polarity of charge generated ...

As stated the problem is probably not well enough constrained. Given the specification, the way you get minimum temperature out is to pump as much volume as you can through the primary and then ...

$$\text{Absolute maximum efficiency} = \text{Carnot Efficiency} = \frac{T_{hot}-T_{cold}}{T_{hot}}$$ where all temperatures are expressed in degrees Kelvin (= degrees C + 273). A very well built and ...

As an upper limit - the maximum power transfer theorum says maximum power is transferred when energy in the flywheel and the mass are shared equally. Mass energy becomes 0.5 x m x v^2 and max height ...

Briefest start. Written from a hosp[ital bed just post operation :-) - better could follow if useful. Solar loading will be peak in hours around noon. Angles shift across year. Find your site 0n ...

100 lbm =~ 45 kgm. Wattage =~ kg x metres_vertical x 10 / time_seconds. So per metre of head, power = 450 Watts / seconds_to_lift. A battery electric drill (or even a mains drill) with a "drum" ...

Independent of what you are imaging, the ratio of object dimension to it's image dimension is a function of the lens focal length and the distance to the object. Knowing the sensor dimensions ...

What speed and Power must the dc motor provide to move a wheelchair at above specifications. Wheel RPM = chair_speed / Wheel-diameter x 60 Motor speed = wheel speed/Gear_ratio. Motor power = ...

I've worked on products designed by others which used injection moulding so while not an expert (and my terminology usage will be terrible) , do have a good feel for what may be attainable. I'd ...

Regulatory requirements will usually stipulate a mounting that will meet uplift conditions. Uplift is very approximately proportional to velocity-cubed normal to panel (eg under it facing up - so ...

The portable angle grinder that I saw them using on TV looked very effective. In the hands of a competent workman the risk of damage is minimal. With a cutting blade this is more a "geared metal saw" ...

I get 115.647 = 116 ie their answer. What you are doing wrong (in this problem and your other recent one) is going too fast and not visualising how the data given translates into the real world ...

Your C to F conversion is correct for a different question. The Celsius and Fahrenheit scales have their zero points offset by a factor equal to 32 F degrees and this has to be allowed for when ...

There is no good reason to think that Qualcomm's QC people did not detect the problem. It's what you do about it that is the problem. That there is or ever was a problem is denied by Qualcomm, some ...

Ceiling fan blades are usually rather crude airfoils - you won't find one in a NACA catalog :-). In many cases a certain amount of violence may be wrought on them without too much fear of disaster. ...

If the meter is correctly connected between the charger and the phone then it will show the current that the phone as a whole is drawing. However, that does not mean that it necessarily shows the ...

In SI units the measure of "amount" of electrical energy is the Joule. Energy is a measure of "work done". Energy can be (and often is) expressed in terms of 'rate of doing work'. The rate at which ...

I have a limited understanding of the subject, having investigated it for a specific project some while ago. That said - I understand that the general 'opinion' is that well below Re = 100,000 ...

You have addressed many of the main points - it's really just "a matter of engineering". If you take 6V out from the top of the right hand battery and 12V from the 2nd contact down (12V output of ...

The arrows on your diagram are intended as a visualisation aid but, in this instance, you are better off without them. Torque is (effectively) conserved. Applying a torque impulse to a body "in free ...

A diagram would help. A sliced cylinder suggests parallel disks on a common shaft. "Top and bottom" suggests a vertical axle - is it? Inner ones may also mean vertical. How many slices? Are they ...

History for centuries past always depends on who writes it, and the Engineering behind the history is thus somewhat a matter of conjecture, but: The English Longbow and "Clothyard shaft" are said by ...

If the balsa can be measured by contact based methods you can use an arm and roller or roller and plunger or various other displacement based means. If contact based means are not acceptable you ...

This partially an exploration of the question and partially a partial answer, but is not suited to the comment format. The following is "obvious enough" but provides two simple rules to allow you to ...

Converted from a prior comment: Boards in such arrangements usually slide on pairs of tracks, one behind the other. Cords from one board go up over a top mounted pulley and down to the other board. ...