X-rays are a fun example too: your bones block them but not soft tissue, so if you use the right film you can see right through yourself!

I was being overly simplistic. It's a measurement of the rate at which work is done, not the measurement of work itself

Horsepower is the actual power of the engine. Torque is the twisting force. Multiply torque by RPM then by a conversion constant and you get horsepower.

> horsepower is a measure of work done

Horsepower is a unit of power. You need to multiply it by time to get a unit of work (AKA energy).

If pulling a plow requires 1 ton of force at 10 mph then the same plow in the same ground is going to need around 4 tons of force at 20 mph. This means that doubling the speed requires eight times the power.

A very long lifespan would be a headache, read somewhere years ago that our brain can only support 300 years in memory if kept healthy. If that is true I think we'd start forgetting things after 200 years. 300 years we would start sense the world aa if we were plants I suppose.

Amazing thank you!

First thing is the premise of the question. cars don't require that much horsepower. We like and want that much horsepower.

But horsepower is only one part of the equation when it comes to any vehicle, or piece of equipment. The engine usually drives a transmission of some kind, or a pump for hydraulics, etc.

My daily driver has an excess of 300 horsepower. I have a military truck that weighs 8,500 pounds, that has a whopping 92 horsepower. I also have a tractor with a front end loader, that's 38 horsepower, And it'll drag both of them around the yard. It's all about application.

Audible sound runs from about 10 Hz to about 25,000 hz.

Visible light runs from 4 x 10 E 14 hz to 8 x 10 E 14 hz. ( 10 E 14 hz is 100 Terahertz )

I'm not an expert but I bet there are issues of scale here. We're men, not mice, after all.

There's another issue which is discussed in a scifi series called Altered Carbon. Presuming we could have a very long lifespan, imagine what that would do to people as far as careers and retirement planning. It would be a massive disaster.

Thank you!

The measurement isn’t looking at the absolute amount of resistance, its looking at the resistance as measured many times per second and watching for a pattern. The pattern is your pulse. It generally looks like a sine wave, and we filter out measurements that dont fit that type of pattern. Sweat happens, and the total measurement changes over time, the wave might move up or down like a tide on a graph, but its still a wave. Because your pulse exists pretty much within a known range of frequencies. Generally, 40-200 beats per minute. We’re ok to just toss out the measurements that don’t make sense. Its okay if we miss a few - its gym equipment and you won’t notice anyway, we just keep saying the same thing until we can get good data again. If its been too long since we got good data, we just stop trying to measure it. Then you usually re-adjust your hands until the measurement starts working again.

Long story short, its not a perfect way to make a measurement but it works well enough that people can use it. We kinda know what we’re looking for, we know how to measure it, and the user will figure out where to put their hands to get it to display the numbers.

Congratulations! You found a use for vocal Fry!

This makes perfect sense and I had it totally backwards. I think my completely backwards answer is rubbing off on you.

At the very least I now know the truth. Thanks!

This question seems to miss the understanding that horsepower is a measure of work done- that is, some amount of mass multiplied by some amount of distance all divided by some amount of time. (Horsepower a a unit is kinda weird like most US customary units, so you would have to pay around with the numbers a bunch to get mass, distance, and time out of the force, rotational speed, and constant that make up this particular unit)

In an application where your work gets done at a slow speed and doesn't need to change that speed significantly or quickly like towing or farming, a better unit of measurement to use would be in units of force. How much force can this machine apply to this load. For things that rotate, the force is torque.

Horsepower is calculated from torque and rpm. The equation is (torque × rpm)/5252. If all the torque needed is generated at a very low rpm, as is the case with large diesel engines, the horsepower is going to come out small.

Fascinating, can you tell me more please?

I read about epigenetics and how David Sinclair and his team supposedly reversed the clock of some of mice's cells, I don't study the field so I don't understand anything at all, lol.

Also there are Aubrey de Grey claiming to use senolytics, NAD+ injections, and even Telomerase could work to treat the Hayflick limit, extending health and lifespan.

Are David Sinclair/Aubrey de Grey dishonests scams? I mean, can their techniques be replicated by the scientific community? I don't want to believe any treatment until they're actually proven to work.

The speed of something moving away is proportional to how far away it is, so the rate is measured as speed/distance. Speed is distance/time, so ...

They are both waves, but they are entirely different types of waves. Light is an electromagnetic wave, while sound is a mechanical wave.

One of the benefits of sound is that it requires a medium, such as the air to move around. When sound travels through the air and hits a wall, window or curtain, it causes the object it hits to also vibrate and disperse on the otherside.

Light however is mostly reflected off of solid objects. It's worth mentioning that while light doesn't go through walls some electromagnetic waves can. Think something like your internet wifi (typically radio waves), which is just a different frequency and wavelengths compared to visible light. Both are electromagnetic, however.

Yes, you are exactly right...and, the wifi and radio waves ARE electromagnetic waves! they are exactly like visible light just wifi and radio waves, microwaves, etc., moves in a different frequency. Your eyes can only pick up certain frequencies of Electromagnetic radiation so we can only see small amounts of the frequency spectrum but like you said, with the right materials almost all of any radiation can be blocked, it just depends what materials you are using and what frequency the radiation is. All different radiation frequencies are absorbed differently by all materials so it is likely that all frequencies have at least one material where where 99.9% of energy is absorbed and more often than not there are multiple different

As a fellow with dry hands: they don't.

They use the bit of moisture most people have on their hands to measure resistance from one hand to the other. Along that path is your heart and its beating changes the resistance so by measuring it over time the device can tell your heart rate.

But if your hands are dry then they can't get a good electrical connection and don't read anything.

Side Effects.

Most cancer treatment falls in the basket of “Kill the cancer before it kills the patient”.

Your intuition is pretty spot on - light and sound are both waves (light does have quantum behavior as photons sound doesn’t, but when they’re acting as waves they’re similar), and both can be absorbed by materials they pass through - depending on the material some wavelengths are absorbed more, and some wavelengths are absorbed less. Think like how you can hear a neighbor’s TV’s bass easier than speech, for instance.

What you’re experiencing in particular is that the wavelengths you can see and the wavelengths you can hear are impacted by typical construction materials differently. If you could see X-ray wavelengths you’d be able to see through walls just as easily as you can hear through them, for example. Conversely, if your walls were made with noise absorbing foam like are used in recording booths then they would be opaque to visible light and also “opaque” to audible sound waves.

The wifi and cellular signal spreads like electromagnetic waves so they do not have mass which means that they can be blocked entirely like light?

At this point I'd add OP needs a little neurological insight, if he wants to sleep through the noise.

I used to travel a lot for business. I'd often sleep in noisy hotels. The recommendation then was to play a radio detuned a bit from the station. The dull meaningless noise would mask the external noises and sleep would come easy.

These days I just play Stephen Fry reading Arthur Conan Doyle's "Sherlock Holmes".

My audio book app goes to sleep after 20 minutes. If I'm still awake, I hear it play a ping 1 minute before it fades out and pauses. If I then shake my phone - the app detects the shake and resets the timer clock to 20 minutes. I've never heard the second ping

The difference in what they're waves OF.

Light can get completely reflected of or absorbed by sufficiently thick stuff (how thick is "sufficient" depends) because it can be blocked by atoms from travelling.

Sound, on the other hand, is a mechanical wave. It's atoms moving around. So you need atoms to have sound, and anything made of atoms can transmit sound.

A wall is made of atoms. Atoms in a wall can block light. But atoms in a wall can transmit sound. Hell, solids are better at transmitting some sounds better than air, it's why the old-timey technique of putting your ear to the ground works, because the low rumbling of solid wheels or hoofbeats would travel through ground better than air.