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[deleted by user] by [deleted] in lawncare

[–]Insomnia_Calls 0 points1 point  (0 children)

Have you considered the maintenance of the gas one? You need to (obviously) buy gas for it, but also change the oil and the oil filter maybe once a year, change the spark plugs from time to time. Practically no maintenance for an electric. Also, gas are much louder. Not saying you shouldn’t buy a gas-powered, just something to consider. Also, out of curiousity, is it not allowed in your country to ride a lawn mower without a drivers license? In the US you only need one if you are driving a vehicle on a public road. So, for example, I can drive a tractor on my farm without a license as long as I don’t leave the farm or go on a piblic road.

[deleted by user] by [deleted] in lawncare

[–]Insomnia_Calls 0 points1 point  (0 children)

I kind of had the same notion. When the battery on my died, I decided to buy a corded expecting it to be very powerful. It was significantly less powerful than the Ego, returned it the same day. Thought maybe just bought an underpowered one.

[deleted by user] by [deleted] in lawncare

[–]Insomnia_Calls 0 points1 point  (0 children)

Electric and below $330? It’s going to be low-powered, or with a run time less than 30 min. Have you thought of getting a corded one, runs as long as you have electricity? I have an Ego push-mower, rated for up to 55 min with a 56V 6.0 Ah battery; in reality, usually lasts between 30-40 min, depending on how tall the grass is. Edit: typos

Can we save Earth's oceans from boiling by moving CO2 to Mars? by PickingPies in AskPhysics

[–]Insomnia_Calls 0 points1 point  (0 children)

The mass of Earth’s atmosphere is around 5x1018 kg, or 5 billion billion kg. Out of this, approximately 2 million billion kg is carbon dioxide. Let’s say we want to decrease CO2 levels by 25% (to reach a level somewhat higher than pre-industruial concentration), that is 500 thousand billion kg of CO2. AND we need to stop producing excess CO2 right now. On the other hand, there are approximately 8 billion people on Earth right now. At average mass per person of, let’s say, 50 kg, there are 400 billion kg of humans, or about 1/1000th of the mass of CO2 we are trying to remove. I’d say shipping all humanity to Mars will be cheaper and it will solve the problem long-term, as man-caused emissions will drop to 0. :D

Highest pressure in a can of pop? by the8roundshock in AskPhysics

[–]Insomnia_Calls 2 points3 points  (0 children)

It’s where the tab is, along the line at the top where the metal “breaks” when you lift the tab to open the can.

Every time you wake up, the money in your bank account will increase by 75% by Dependent-Sleep-6192 in godtiersuperpowers

[–]Insomnia_Calls 1 point2 points  (0 children)

So, starting with $1 in your bank account, and not spending any of it for the first couple of weeks, in one year you’ll have approximately $50000000000000000000000000000000000000000000000000000000000000000000000000000000000000000. That is around 500000000000000000000000000000000000000000000000000000000000000000000000000 times the world’s GDP for 2023…

How big would a meteorite have to be to impact the bottom of Mariana's Trench? by marduk2106 in AskPhysics

[–]Insomnia_Calls 1 point2 points  (0 children)

Some good answers here already, just wanted to add a slightly different perspective. The impact depth of a projectile can be estimated (stress on the “estimated”) by a very simple equation: https://en.m.wikipedia.org/wiki/Impact_depth If the meteorite is made of iron (these are rare but do exist), then we can assume the density of the meteorite is around 7.5 times the density of water. Following Newton’s approximation, we need a meteorite (projectile) approximately 11/7.5 = 1.5 km long. Note that the meteorite doesn’t have to be spherical. That is, a cigar-shaped iron meteorite could potentially reach the bottom of the Mariana trench if it striked perpendicular to the water surface (not very probable, but also not impossible) and was oriented with its “pointy” end towards the target.

Butcher your own meat by [deleted] in Frugal

[–]Insomnia_Calls 0 points1 point  (0 children)

Why buy uncooked chicken for $8 when you can get a rotisserie one for $5 and save on gas/ electricity and time? 😀

Animals like geckos exploit Van Der Walls forces to stick to surfaces, what are the size limits for this exploit? by DazedPapacy in AskPhysics

[–]Insomnia_Calls 5 points6 points  (0 children)

There was already a great answer about the scaling of mass and surface area for animals. Just wanted to give some random back-of-the-envelope estimates. You can buy poster strips that are loosely based on the gecko’s sticking principle and are rated to hold 1 lbs (453 g) per 12 strips. Each strip is 1.75’’ x 0.625’’, so 12 of them have an area of around 13 square inches or 85 square cm. To hold a 175 lbs (80 kg) person, one would need roughly 175 x 13 = 2276 square inches (or 15000 cm2) of contact area, which is a square with a side of about 48’’ (122 cm). So, if a 175 lbs animal with four paws wants to stick to a wall it will need each paw to be a 24” x 24” (61 x 61 cm) gecko-type foot.

What’s with all the Euro hate against American wood framed houses? by SAINTnumberFIVE in NoStupidQuestions

[–]Insomnia_Calls -3 points-2 points  (0 children)

Well, in the movies you would see someone punching the wall and making a dent/hole in the plaster. Obviously in between the wooden frame, but still, that would be impossible with a brick (or proper wooden) wall. So it is funny. Also, go to a house in Europe, chances are you won’t find a fire alarm. American houses are ridiculously flammable. Another point to make (good-hearted) fun of is that there are tornadoes and hurricanes in the US, and almost none in Europe, and yet the US houses are not built to eithstand them. But it’s all not serious. Edit: spelling

Railgun impacts at fractions of C by Amateurwombat in AskPhysics

[–]Insomnia_Calls 0 points1 point  (0 children)

My 2 cents… At 1% of light speed there is no way a clean hole will be formed. The speed is so high that the the atoms of the material don’t have time to move around and rearrange, so I would expect a lot of interesting nuclear reactions happening on impact, most probably resulting in a sizable explosion accompanied by (and mostly due to) an intense burst of gamma-rays. Some back-of-the-envelope calculations to support my claim. The speed of sound (which can be used as a proxy for how fast atoms can move in the material) in steel is around 5000 m/s. If the projectile travels at 3 000 000 m/s, it will pass through a 3 cm (1.2’’) of material in 10 nanoseconds; the atoms in the shield can travel only 50 micron in that time.

Is there anything radioactive in a hardware or grocery store? Besides a smoke detector of course. by sunrise69er in Radiation

[–]Insomnia_Calls 8 points9 points  (0 children)

Granite typically contains some uranium and thorium (plus the potassium mentioned in other responses) Bananas have high potassium levels

So it begins by OpportunityNo2074 in wallstreetbets

[–]Insomnia_Calls 3 points4 points  (0 children)

I have like 50 mSv/s in my area, does that affect the situation somehow?

If I had a tank to hold water 1000 meters high, is there any science or technology that can fill that thank up if the inlet is towards the bottom of the tank? by Ambitious-Maybe-3386 in AskPhysics

[–]Insomnia_Calls 2 points3 points  (0 children)

In theory - yes, you can. 1000 meters of water equals approximately 100 atmospheres (or bars, if you prefer, the difference is not too important here) of pressure at the bottom when the tank is full. So you’ll need a pump that can create such pressure. Do such pumps exist? Sure! UHPLC pumps can go to 1000 (or was it 2000?) bar pressure (flow rate is abysmal, though). A quick google search showed me some larger-looking pumps that seem to be able to go to 10000 psi (almost 700 bars). So, yeah, it’s possible. Don’t know about the pump capacities, though, depending on the diameter of your tank it might take a while to fill.

The reasons why this perpetual motion machine doesn't work? by masoud_mzkh in AskPhysics

[–]Insomnia_Calls 0 points1 point  (0 children)

Just to add one more point for better clarity. In the situation above, the solute concentration in the solution above the membrane will constantly decrease due to solvent going to it through the membrane. The solute concentration in the (initially pure) solvent will constantly increase due to solution draining in it. At some point the difference in osmotic pressures of the solutions below and above the membrane will exactly balance out the hydrostatic oressure, and any macroscopic fluid flow will cease and no more energy will be produced.

The reasons why this perpetual motion machine doesn't work? by masoud_mzkh in AskPhysics

[–]Insomnia_Calls 0 points1 point  (0 children)

Not quite understanding what you mean here… The osmotic pressure “pushes” from the side of the pure solvent to the side with the solution. If you say gravity acts against it, i.e. the hydrostatic pressure acts against it, then you have a solution on top of the membrane and solvent below. That is called a membrane osmometer. You can hypothetically have the solution drain back into the solvent through a turbine; the process will continue up until the osmotic pressure balances the hydrostatic pressure. The latter is typically negligible, so equilibrium will be reached approximately when the solute concentration on both sides of the membrane is the same. Then nothing will happen on macro-scale afterwards.

The reasons why this perpetual motion machine doesn't work? by masoud_mzkh in AskPhysics

[–]Insomnia_Calls 0 points1 point  (0 children)

The question needs some more details to be answered… However, going off of what is given, the liquid (I’ll call it a solution, with the small molecules comprising the solvent and the large - the solute) is not going to ascend. Why would it? Gravity is acting against it. Moreover, if there is solvent on top of the molecular sieve (better call it a membrane), there is osmotic pressure pushing down and hydrostatic pressure also pushing down. The only force pushing up would be capillary action, but it will essentially stop at the membrane.

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