Latest news with #ACDC
WIRED
3 hours ago
- WIRED
AC or DC: Which Is Better?
Aug 1, 2025 8:30 AM Your gadgets run on direct current, but the electricity in your home is alternating current. What's up with that? Photo-Illustration:As the story goes, the rock band AC/DC took its name from a label on an old sewing machine in the Young brothers' home. It must have meant that the machine could run on either alternating-current or direct-current electricity. Today, all the newfangled electronic devices in our homes run only on DC power—even lighting fixtures, now that LEDs have replaced incandescent bulbs. But wait. The electricity that comes out of your wall socket is alternating current. That means each device needs to convert AC power to DC, as well as reducing the voltage to the much lower levels used in digital circuits. So you might well ask: Wouldn't it make more sense to have DC outlets in your home? That's a great question, and it's actually one that sparked a big debate back in the early days of electrification. Thomas Edison favored DC circuits, but Nikola Tesla thought AC circuits were the way to go. Clearly Tesla won that argument. Let's see why! What Is Electricity? Electricity is a flow of electrons through a conducting material like a metal wire. You can kind of think of the electrical grid as a system of rivers and streams with current flowing through them. In a river, a difference in elevation causes water to move downhill; in a power line, the force driving the current is voltage —a difference in potential energy between two points in a circuit. That analogy works for direct current, anyway. But in most grids, electrical power is transmitted with alternating voltage. That means the negative and positive poles flip back and forth, causing the electrons to endlessly lurch forward and backward instead of traveling in a continuous stream. As you can imagine, that makes alternating current more complicated to deal with. So Edison had a point: Direct current is much simpler. In fact, anyone can make a DC circuit. All you need is a battery and a wire to connect the positive and negative electrodes. You can even make your own battery. Just get two different metals, like zinc and copper, and stick them in opposite ends of a potato. The acid in the potato juice reacts differently with the two metals, creating a tiny amount of voltage—enough to light up a small LED. DC is easy. Direct-Current Toaster For example, suppose you wanted to create a DC toaster. A toaster is basically a box with a wire inside that gets hot when current runs through it. And let's say this toaster requires 1,000 watts of power. Oh, power? That's the time (t) rate of energy (E). So if you put 1 joule of energy into a wire in 1 second, that would be 1 watt of power (P): For electrical power in particular, we can calculate that as the product of the electric current (I) and the voltage (V): With that, we can draw a simple toaster circuit diagram: The nichrome wire inside the toaster is not a good conductor. It impedes the flow of current, causing the wire to heat up. So it's basically a device for converting electrical energy into thermal energy. In the diagram above, R stands for the amount of resistance, which is measured in ohms. So let's say our DC power supply runs at 10 volts. We can use this to find the level of resistance needed to get our toast nice and toasty. There is a relationship between the current (I) and voltage (V) for a resistor called Ohm's law, and that gives us the following expression for power: With 10 volts, we need a resistance of 0.1 ohms (which is tiny) to get a power of 1,000 watts. But wait—it's not just the heating element inside that creates resistance in the circuit. The power cord that you plug into the wall also has resistance. The copper wire inside the cord is a good conductor, but the length of the cord itself increases the resistance. To make things easy, imagine that the power cord also has a 0.1-ohm resistance, so the total resistance in the circuit is 0.2 ohms. That means we'd get a lower electrical current, and the power to the toaster would be just 250 watts. That's going to be some un-toasty toast. To fix this, we have to increase the voltage of the power source. Let's ramp that up to 100 volts. In that case our toaster could be 10 ohms, so the 0.1-ohm power cord won't matter much. Well, it's not a problem for a 3-foot power cord in your home. But what about the transmission lines from the power station to your town? These can be over 100 kilometers long. With much longer wires you get much more resistance, which means those wires will get hot and waste energy. Again, the solution is to use a higher-voltage source. Remember P = IV ? That says you can deliver the same power by having a stupid-high voltage with stupid-low current. Yes, you solve one problem and it just makes another problem. Suppose the wall outlet is 10,000-volt DC. Oh, but you want to charge your phone, and it needs 5-volt DC. How do you do that? OK, there is a way to make it work. You could put a large resistor in series with your phone and it would convert electrical energy to heat. But again, that's just throwing away energy. Alternating-Current Toaster So what happens if we switch to alternating current? Remember, AC circuits are created by flipping the positive and negative poles back and forth, so the voltage alternates between a positive value and a negative value (meaning the direction of electron flow changes). Here is a plot of voltage as a function of time for the two types of current. The DC source has a constant voltage, so that's the flat blue line above. The AC source (red) has a voltage that oscillates between +10 and –10 volts, and there are times when the voltage is actually zero. In this made-up example, you can see that the voltage switches eight times in half a second. Real household AC varies, but in the US it averages around 120 volts (plus and minus) with a frequency of 60 hertz. If we take our toaster and plug it into a 60-Hz AC outlet, it'll run just fine. Since it works by just making a wire hot, it doesn't matter if it has DC or AC current—either way it gets hot. Same for incandescent light bulbs. In fact, they're really not very different from toasters; it's just that the thin tungsten wire in a bulb gets so hot (up to 4,500 degrees F) that it glows and produces light. AC Power Is More Efficient With AC, we still have the same problem with long power lines. You need to have high voltage and low current so you don't lose too much energy from hot wires. But AC has a nice advantage: It's easy to take that high voltage and change it to a low voltage. This is possible because of the oscillating nature of the current and Faraday's law of induction. Faraday's law says that if you change the strength of a magnetic field inside a loop of wire, you will produce an electric current. In the clip below, you can see that when I stick a strong magnet into a coil of wire or pull it out, the current level (measured in amps) jumps up. You can also do this without a magnet if you use two coils of wire. In the video below, I'm connecting and disconnecting a little coin battery to a primary coil. (You can't see the coils, but they're inside the small gray box in the foreground.) The secondary coil isn't connected to any power source. But the changing current in the primary coil makes a changing magnetic field, and that induces a current in the secondary coil. Even with this tiny battery you can see that I get a big induced current. Check it out: But that's not all! We can change the voltage induced in the second coil by changing the ratio of the number of loops in each coil. If the induced coil has 100 loops and the primary coil has 1,000 loops, the induced voltage will be 100/1,000 or 0.1 times the input. If you reverse that, you can get an output voltage that is 10 times the input. We call this a transformer (because it transforms the voltage). They are kind of a big deal. Here's what a small one looks like inside: This is one of those 'power bricks' that all your gadgets use to plug into a wall socket. The two coils are side by side, and you can see that the one on the right has more 'turns' than the one on the left. So, if you have a 120-volt AC input, the output will be lower (in this case it's 12 volts). There's some other stuff in there that takes that lower-voltage AC and turns it into a DC output; that's called a voltage rectifier. Just to be clear, you can't use an AC transformer with a DC circuit. I mean it's technically possible to take a DC input, convert it to AC, and then transform it—but why do the extra stuff when you can just deliver AC power to houses? That's exactly what we do. When you see those giant high-voltage transmission lines, they are super-high-voltage AC circuits. So here's how it works. You have some power station that runs on fossil fuels or hydroelectric or whatever. You need to make this an AC output and then ramp up the voltage to something crazy like 100,000 volts. This means you can send it on the long power lines at very low current so there isn't much power loss. When a power line gets to a town, it goes into a substation. This is basically just another giant transformer that reduces the AC voltage to something more manageable, like 10,000 volts. Finally, the current goes through one more transformer to get it to the 240-volt AC that enters your house. Big appliances like clothes dryers use the whole 240 V, and for your electrical outlets that gets cut in half to give you 120 V. But none of this would be possible with DC power. It just wouldn't be practical. AC rules!
ABC News
6 days ago
- Entertainment
- ABC News
Here's which Hottest 100 tracks have been covered on Like A Version
The Hottest 100 of Australian Songs may not have included Like A Version performances (they got their own countdown in 2023, to be fair), but a whole heap of tracks in the list have been covered in the triple j studios. Over the last 20-odd years of Like A Version sound-tracking our Friday mornings, hundreds of songs have been covered. Among those include these 53 Australian tracks that you firmly believe are the best our country has ever produced. That's more than half of the countdown! From AC/DC to DMA'S, Missy Higgins to Regurgitator, here are all of the Hottest 100 of Australian Songs placegetters who have been covered in the Like A Version studio. #1 INXS - Never Tear Us Apart: covered by True Live (2008) and Allday (2014) #4 Missy Higgins – Scar: covered by 67 Special (2006) #5 Crowded House - Don't Dream It's Over: covered by Middle Kids (2017) #6 Powderfinger - My Happiness: covered by Clare Bowditch (2010) and Ball Park Music (2017) #9 Paul Kelly - How To Make Gravy: covered by Luci Brasi (2016) #10 Gotye - Somebody That I Used To Know: covered by Eskimo Joe (2011) #11 The Temper Trap - Sweet Disposition: covered by Space Invadas (2010) #12 The Angels - Am I Ever Gonna See Your Face Again: covered by Seabellies (2010) and Dune Rats & Friends (2022) #13 AC/DC - Thunderstruck: covered by Odette (2022) #15 John Farnham - You're The Voice: covered by Bec Sandridge (2017) #18 Midnight Oil - Beds Are Burning: covered by Anti-Flag (2008) #19 Tame Impala - The Less I Know The Better covered by Ngaiire (2015) #20 Angus & Julia Stone - Big Jet Plane: covered by Tuka (2015) #22 Paul Kelly - To Her Door: covered by Gyroscope (2008) #24 Empire Of The Sun - Walking On A Dream: covered by Boy & Bear (2011) #25 Hunters & Collectors - Throw Your Arms Around Me: covered by Ayla (2015) #26 Flume ft. kai - Never Be Like You: covered by Polish Club (2017) #27 Kylie Minogue - Can't Get You Out Of My Head: covered by Dallas Crane (2007), The Flaming Lips (2009), Peking Duk (2014) and PANIA (2023) #28 Silverchair - Straight Lines: covered by Glades (2018) #29 The Church - Under The Milky Way: covered by Josh Pyke (2008) #31 AC/DC - Highway To Hell: covered by The Bellrays (2006) #32 Natalie Imbruglia – Torn: covered by Alex Lahey (2017) #34 Spacey Jane - Booster Seat: covered by Asha Jeffries (2024) #35 ICEHOUSE - Great Southern Land: covered by Little May (2015) #39 Australian Crawl — Reckless (Don't Be So): covered by Children Collide (2010) and Angie McMahon (2024) #40 Violent Soho — Covered In Chrome: covered by Northeast Party House (2016) #42 Gang Of Youths — Magnolia: covered by Odette (2018) #44 Nick Cave and the Bad Seeds — Into My Arms: covered by Jess Ribeiro (2008) and Emma Louise (2016) #46 Bag Raiders — Shooting Stars: covered by Flume (2022) #48 Vance Joy — Riptide: covered by The Griswolds (2014) #51 Matt Corby — Brother: covered by Thundamentals (2012) #52 Missy Higgins — The Special Two: covered by Dear Seattle (2019) #53 Thelma Plum — Better In Blak: covered by Beddy Rays (2021) #54 Divinyls — I Touch Myself: covered by Behind Crimson Eyes (2006) and Lime Cordiale (2019) #55 The Presets — My People: covered by Basement Birds (2010) #58 The Avalanches — Frontier Psychiatrist: covered by Methyl Ethel (2021) #59 INXS — Need You Tonight: covered by Husky (2012) #61 Chet Faker — Talk Is Cheap: covered by Timberwolf (2017) #63 Redgum — I Was Only 19 (A Walk in the Light Green): covered by The Herd (2005) #65 Ocean Alley — Confidence: covered by Adrian Eagle (2019) #67 Regurgitator — ! (The Song Formerly Known As): covered by 360 (2011) and Client Liaison (2014) #75 The Church — The Unguarded Moment: covered by Ruby Fields (2019) #78 Eskimo Joe — Black Fingernails, Red Wine: covered by Polaris (2020) #80 Empire Of The Sun — We Are The People: covered by Metronomy (2009), Little Red (2010) and Tia Gostelow (2018) #81 You Am I — Berlin Chair: covered by Holly Throsby (2008) #83 Ben Lee — Cigarettes Will Kill You: covered by Alpine (2015) #85 DMA'S — Delete: covered by Sticky Fingers (2015) #86 Gotye — Hearts A Mess: covered by Missy Higgins (2012) #87 Gang Of Youths — The Deepest Sighs, the Frankest Shadows: covered by Gretta Ray (2021) #91 The Whitlams — No Aphrodisiac: covered by Horrorshow (2017) #93 The Avalanches — Since I Left You: covered by REMI (2013) #94 Flight Facilities — Clair De Lune covered by The Kite String Tangle (2014) #98 Nick Cave and the Bad Seeds — Red Right Hand: covered by FIDLAR (2013)
Globe and Mail
7 days ago
- Business
- Globe and Mail
ProFrac Holding Corp. Announces Second Quarter 2025 Earnings Release and Conference Call Schedule
ProFrac Holding Corp. (NASDAQ: ACDC) ("ProFrac" or the "Company") announced today that it will report its second quarter 2025 financial results prior to the Company's conference call, which will be webcasted on Thursday, August 7, 2025, at 11:00 a.m. Eastern / 10:00 a.m. Central. To register for and access the event, please click here. An archive of the webcast will be available shortly after the call's conclusion on the IR Calendar section of ProFrac's investor relations website for 90 days. About ProFrac Holding Corp. ProFrac Holding Corp. is a technology-focused, vertically integrated and innovation-driven energy services holding company providing hydraulic fracturing, proppant production, related completion services and complementary products and services to leading upstream oil and natural gas companies engaged in the exploration and production ("E&P") of North American unconventional oil and natural gas resources. ProFrac operates through three business segments: Stimulation Services, Proppant Production and Manufacturing, in addition to Other Business Activities. For more information, please visit ProFrac's website at
Yahoo
23-07-2025
- Entertainment
- Yahoo
Legendary '70s Rock Band Urged by Fans to Retire After Viral Concert Video — 'It's Sad'
Legendary '70s Rock Band Urged by Fans to Retire After Viral Concert Video — 'It's Sad' originally appeared on Parade. AC/DC has been rocking stages for over 50 years, but after recent concert footage from their "Power Up Tour" went viral, some fans are questioning whether it's time for the legendary band to call it quits. The footage, captured at Gillette Stadium on May 4, shows the group mid-performance on their North American leg of the tour. In the viral clip — now racking up over 150,000 likes and nearly 3 million views — guitarist Angus Young takes center stage in his signature schoolboy look, wearing blue velvet shorts. He energetically chants and shouts into the mic during a live version of "T.N.T." However, it wasn't Angus' outfit that caused a stir in the comments. Instead, fans zeroed in on lead singer Brian Johnson's vocals, claiming he sounded off-key. "I was going to get tickets until I saw this,' one person wrote. Another added, 'yeah lads it might be time to stop." The sentiment echoed through hundreds of comments — with some fans expressing disappointment in a show they hadn't even attended. "I really wanted to see them this year.. now I dont. thank you," one user said. Another wrote, "Gotta say, Angus is really pulling the load on this tour. They'll always be my favourite band by far, but I'm sitting out this tour." While some fans called for retirement, others were quick to defend AC/DC. "Idc if they sound bad in this. These guys are absolute legends…(still) doing this into their 70's is incredible," one TikTok user wrote. Another fan commented, "why are people hating, they are adorable. i'd go to see them, they are doing so well to be touring at this age." Despite the divided opinions online, the tour has received praise from critics and major publications. Rolling Stone Germany reportedly said that "AC/DC electrified the stadium with a thunderous performance that left the crowd roaring for more," and The Guardian described the show as "a poignant lesson on the power of rock'n'roll." AC/DC has been performing since the 1970s, and they don't seem to be slowing down anytime soon. The band just announced an extension to their tour, adding five more shows in their home country of Australia to close things out. Even as the rockers age, one thing remains undeniable — they're still bringing high-energy performances of iconic hits like 'Thunderstruck,' 'Back in Black' and 'You Shook Me All Night Long.' If you manage to snag tickets, you may hear a few flat notes here and there, but the amps are loud enough to drown out your complaints anyway. Legendary '70s Rock Band Urged by Fans to Retire After Viral Concert Video — 'It's Sad' first appeared on Parade on Jun 27, 2025 This story was originally reported by Parade on Jun 27, 2025, where it first appeared. Solve the daily Crossword
Sydney Morning Herald
18-07-2025
- General
- Sydney Morning Herald
Do Australians have the best possible version of English?
Language students in Britain, it was reported this week, face a challenge because the word 'sorry' is used so often and means so many different things. Sometimes it is a genuine apology, sometimes it means the speaker is not sorry at all ('I'm sorry if you took it that way'), and sometimes it means you simply can't hear what's being said ('Sorry?') Fair enough. The word poses difficulties, both there and here. In this country, though, the complexities of 'sorry' are joined by other linguistic problems which must be overcome by the eager student. In fact, when compared with English English, ours is simply the more complex and nuanced language. For a start, there are the many varieties of the word 'mate', ranging from the convivial to the downright threatening. There's the ALP 'mate', for example, which has several repeats of the letter 'a', as in 'maaaaaate'. It means you are about to lose preselection or be dumped from the Prime Ministership. There's the terse 'excuse me, mate' when someone's blocking the entrance to a building, and the sunny 'thanks, mate' when they finally make way. Meanwhile, 'mate', when used by a mechanic, means: 'I've judged that you are the sort of chap who knows nothing about motor vehicles and so have elected to charge you double.' Sharon is Shaz. Darren is Daz. Aggression is agro. ACDC is Acca Dacca. Breakfast is brekky. Vegetarian is vego. Barbecue is barbie. Could I use that meaning of 'mate' in a sentence? Certainly. Here's the mechanic: 'I've had to completely replace the manifold, the big end and all the grommet pins, so – mate, ah – it comes to $2,497. Let's call it $2,496 for prompt payment.' All he's actually done, you later learn, is polish the tyres. Of course, when used in a workplace or at a neighbourhood barbecue, 'mate' is much less hostile. Instead, it's Australian for 'I've forgotten your name, but I'm still willing to fetch you a drink. So, what will it be, um, mate?' The word 'bastard' is even more complex. As I've previously observed, Australia may be the only country in the world where Hitler is described as 'a bit of a bastard', while your best friend is 'a total bastard.' This is due to the Great Australian Linguistic Deflator (GALD) under the rules of which both praise and criticism must be muted to a stupendous degree (except we'd never use a word like 'stupendous'). Under the principles of GALD, the serial philanderer who abandoned his kids and stole all the wife's money, before running off to Canada with a trapeze artist from Cirque du Soleil, is 'a bit ordinary in the husband stakes'. Dame Joan Sutherland, by contrast, was 'not exactly a slouch when it came to belting out a tune'. Then we come to names. In Britain, the longer your name, the better you are regarded. Call King Charles by his complete handle and you'll be there for some time. He's 'Most High, Most Mighty, Most Excellent Monarch, Our Sovereign Lord, Head of the Commonwealth, Defender of the Faith, and Sovereign of the Most Noble Order of the Garter'. That's 28 words, and they're just getting limbered up. By contrast, in Australia, success is measured by the brevity of your title. A successful prime minister, such as Robert James Lee Hawke, is known as 'Hawkie', while an unsuccessful one, while an unsuccessful one, such as Scott John Morrison, is known as Scott John Morrison (he tried his best with 'Scomo' but it never took off). Loading Likewise, the singers Barnsey and Farnsey. If only they were a little more successful, they might one day find themselves referred to as simply 'Ba' and 'Fa'. Keep going, lads, and perhaps your time will come. No one, it seems, wants to leave their mouth open for long. Not with this many flies. That's why everything, simply everything, should be shortened.
