Why don't birds get electrocuted sitting on power lines?

Current flows in a loop[ which means the circuit is closed]. A bird sitting on a transmission line does not complete the circuit. If the same bird keeps one leg on one line and another leg (or any part of its body) on another line(or the neutral points), then it will get roasted.

---

Consider this circuit where a bird sits on the wire:

The values R1 and R2 are resistances of the line. Electricity takes the path of least resistance. The two legs of the bird which is perched on the same line does not complete the circuit. The R_Bird( resistance of the bird’s body) is much higher than that of the line, so the bird might not experience high current. The potential difference between the two legs of the bird is same( since the resistance of the line is the same throughout).The current flows on.The bird is safe.

Now consider this scenario:

A bird sitting on a line decides to fly away and raises the wings. With one wing touching the neighboring line and the leg on the first line, this creates a closed circuit. Thus electricity (following the path of least resistance) will detect a potential difference between the wing (which touches the other line) and the leg(which is placed on the first line). The current tries to take on that path creating a short-circuit. Eventually the bird gets zapped and falls off the line. Now the current will continue to flow on.

---

The lesson we learn here is that when ever we play with electricity, make sure you (your body) does not close the circuit. When we poke our fingers into an electrical socket we get shocked because our body will offer a lower resistance . Thus a potential difference will be created between your finger and the feet( which is placed on the floor acting as a neutral point).

Is it bad to charge your phone over night?

As we know, our smartphone batteries are bad as they barely last a day. At the earlier days when we buy it, it’s the fault of smartphone manufacturers. But what about several days later? It’s to some extent your own fault for charging it wrong this whole time. For example, charging phone overnight.

​

Firstly, let’s have a look at the following saying: charging phone overnight, or more specifically, charging phone when it’s already fully charged, will keep it in a high-stress, high-tension state, which will surely do wear down the battery with lasting damage at the same time.
So, is it true? Is charging phone overnight bad?
Well, you’d better ignore that. We couldn’t be more wrong.
And the truth is that Charging phone overnight will not harm your battery in the slightest. Any device with a Lithium Polymer battery must incorporate a charging circuit that will cut off charging power when the battery reaches 100%.
Besides, the smartphone battery is as smart as the phone itself. Apple, Samsung and all the top tech companies, almost of whose products use lithium-based batteries.

That aside, however, Lithium-ion batteries don’t need to be charged all the way to 100%. While your phone runs troughtout the night, it loses battery life. And this will cause the charging mechanism to kick in over and over again as amounts of battery drain occurs during standby when checking emails, receiving text messages, and updating various apps while you sleep.

Let’s take an example. If you head to bed at 11 p.m. with a battery percentage in the single digits, your phone will be fully charged by 2 a.m. If you wake up at 6 a.m., that’s 4 hours that your phone stays plugged in with a full battery.

So what is the optimal way to charge your phone? That is to keep them charged between 50 and 80 percent.

Additionally, we have to mention Charge Cycles, that is, your battery goes from empty or near-empty to full. Every phone battery has a limited number of charge cycles before the end of its life. An iPhone has about 500 charging cycles. When charged up from 90%, only 10% of a complete charge cycle used. Whereas, when charged up from zero, then a complete charge cycle done. Or you’ll actually shorten your battery life if you do so.

Surely, here is another good idea for charging, or portable charging. And that is to take a power bank in hand, in pocket.