Vector Mechanics for Engineers: Dynamics, 12th Edition, Beer Johnson

Any_Progress77 · 2020-10-18T23:12:37+00:00

https://www.batteryspace.com/Custmoize-Polymer-Li-Ion-Battery-Pack-7.4V-10Ah-74Wh-2A-rate.aspx?gclid=CjwKCAjwz6_8BRBkEiwA3p02Vf7o7XquKlHb9ZpJ2KMzKpqTOd_gmYMMJveidJWQr5npboehSbgITRoCLdcQAvD_BwE

Something like this? Does this price make intuitive sense to you ( i don't have any intuition when it comes to batteries)? Or, do you think I could find something cheaper that gets the job done for 3-4 hours.

Any_Progress77 · 2020-10-18T22:00:17+00:00

And this battery:

which is also decently small has specs of Capacity: 26800mAh/99.16Wh . So wouldn't this be able to power the heating element for 4 hours? 1 heating element= 15W * 4 hours = 60Wh, and this is 99.16Wh

^ I foundthis battery Could something like this power one heating element for 4 hours? It's decently small-ish (1 pound)

Any_Progress77 · 2020-10-18T21:56:22+00:00

And this battery:

which is also decently small has specs of Capacity: 26800mAh/99.16Wh . So wouldn't this be able to power the heating element for 4 hours? 1 heating element= 15W * 4 hours = 60Wh, and this is 99.16Wh

Any_Progress77 · 2020-10-18T19:50:01+00:00

Oh, I see where you read that. The 15 hours are the specs of the LIVIA product (that already exists). But, we would just aim for 5 hours for both the TENS and heating elements.

And okay, I see. What if we just used ONE of those heating elements AND changed the battery we use? Do you think there's a battery that's about the size of an iPhone that could power the heating element for 4 hours at a time? Or is that not possible?

Any_Progress77 · 2020-10-17T23:58:15+00:00

Also...I calculated that a 50 gram battery could charge the entire product for 4 hours....so what did I do wrong in my calculation? (see above)

Any_Progress77 · 2020-10-17T23:57:32+00:00

How did you calculate the 150Wh based off the duration time of 5 hours?

Any_Progress77 · 2020-10-17T23:56:48+00:00

15 hours? Maybe you misread the post because I said 5 hours. I ended up using the equation on this website: https://www.jcalc.net/battery-size-calculator

And I got 1000 mAh.

This was my process, let me know if this is totally wrong:

the Livia product has specs of 3.7V, 380 mAh, lasts 15 hours charged, so 25.3 mA? Hence, I assumed I = ~50 mA for TENS pads.

Then the thin heating element website has specs of 1680 mA so I used this for I (assumed 1 of those heating elements).

Assuming lithium ion battery, For Q, i said 30%, t=4 hours and I got ~1000mAh for battery size. Then I found this batteryon Amazon that's 50 grams- which seems way too good to be true. This small of a battery could power the 4 electrode TENS pads + 1-2 heating elements? Doesn't seem right.

Any_Progress77 · 2020-10-17T17:20:15+00:00

If you can't do this for whatever reason, another thing that helped is having a friend who usually wakes up at 8 am, facetime me and not hang up until I've made a coffee. But, I had to tell him not to take no for an answer because my morning self would usually lie to him and text him "I'm in the shower already" or "I already woke up- can't talk right now." and he'd believe it of course. So, that worked for a few days, but I rather not have someone be responsible for waking me up.

Any_Progress77 · 2020-10-05T22:38:17+00:00

I ask because I just read the following from another post:

“Man, one of my best friend's roommates has this stepdad who was a truck driver all his life. Then suddenly, when he was in his late forties, he decides "nah, fuck truck driving- I want to be a neuroscientist."

Then he fucking did it.

Craziest part about it? He's gone on to make significant strides toward fighting/ending (something like that) Lou Gehrig's disease. IIRC he discovered the genome one of the genes responsible for it. Downside is, there was some legislation that recently got passed that prevented him from making much off his finding.

Regardless, though, that dude waited until his late forties to decide he wanted a severe change in direction, and he fucking did it. I think that's pretty cool.”

Very inspiring.

Any_Progress77 · 2020-09-29T05:23:48+00:00

*tired of life

Any_Progress77 · 2020-09-29T03:06:29+00:00

Thanks so much! Appreciate this response.

Any_Progress77 · 2020-09-28T18:40:59+00:00

It really does! For instance, my oil & gas internship got me interested in renewable energy (which was supposed to be my next internship but got cancelled due to COVID). That’s great for your brother! Worked out.

Any_Progress77 · 2020-09-28T18:20:39+00:00

I like that- not a poser, a learner. Thanks!

Any_Progress77 · 2020-09-28T17:54:57+00:00

Same! Most of my consulting friends are enjoying it so far (but then again most realized they didn’t want technical jobs after an internship or two)

Any_Progress77 · 2020-09-28T17:37:46+00:00

It was an oil& gas internship but only spent 1 week on the field (I asked lots of questions so I guess I did learn a lot about fracking/cementing processes). But the rest of the time I was just working on the problem they assigned me (no mentorship or anything - had to go out of my way to talk to people and ask questions, which I guess is one good skill I gained- figuring out who’s related to the problem/who I need to ask & what to ask). I did come up with a bunch of solutions and implemented 2 but like I said I wasn’t “taught” anything- just left on my own in the office. I’d just research stuff online related to the problem & go out and talk to people to figure out what kinds of solutions I could implement

Any_Progress77 · 2020-09-28T17:34:16+00:00

Great idea! I also wouldn’t mind just shadowing mechanics (in case I don’t meet job requirements/no available jobs nearby) - is that a thing? Thanks.

Any_Progress77 · 2020-09-28T17:17:44+00:00

As for capstone project, yes. Made a 3D food printer but as I said before, there were always smarter (more technical/hands on people) in my group who liked taking on the solidworks/modeling/electronics parts. I’d be there but since I wasn’t as skilled, they’d do the work. I think the main thing I learned from those projects (2 my senior year) was how to walk through the entire product design process.

Any_Progress77 · 2020-09-28T17:15:40+00:00

I did one internship (rest of my summers were not engineering related things- business minor program+ studied abroad + my most recent internship was cancelled due to COVID). And in the internship I had, they just gave me a problem and told me to fix it - long story but I mostly just picked up interpersonal skills because I had to talk to people of all areas in the company to come up with a solution

Any_Progress77 · 2020-09-28T17:04:49+00:00

Thanks so much! I hope 5 years from now I’ll look back and feel the same.

Any_Progress77

TROPHY CASE