Lv 783,024 points


Favourite answers18%
  • Power outage while laundry was running?

    My electricity went out midway through running the washing machine. Pretty sure it will resume when the power comes back on, but no idea how long a wait that will be.

    How long can I let the clothes sit in detergenty water?

    If I do have to take them out, what do I need to do with them? Just rinse the soap off in the shower? There's no bleach or other strong chemicals in there.

    3 AnswersCleaning & Laundry6 months ago
  • Buying a bicycle?

    I'd like to start biking for exercise and eventually get in-shape enough to use the bike for short errands.

    I haven't been on a bike since I was a teenager. What do I need to be thinking about as I shop?

    How do I judge which bike is the right size/shape/durability?

    Do I buy from a specialty shop that can help me with that, or do I go to a cheaper store such as Walmart?

    Besides a helmet what accessories do I need for biking on suburban streets?

    4 AnswersCycling7 months ago
  • How is a trade deficit even possible, given the need to exchange currency?

    Scenario 1:

    Alice and Bob are American. Li and Min are Chinese. America produces beef; China produces textiles.

    Alice is willing to pay $20 for a sweater. Li is willing to sell a sweater for ¥100.

    Min is willing to pay ¥100 for a beef steak. Bob is willing to sell a beef steak for $20.

    In this case, Alice and Min trade $20 for ¥100, and both are able to make their purchases. Two products of equal value are exchanged between America and China.

    Scenario 2:

    Alice is willing to pay $20 for a sweater. Li is willing to sell a sweater for ¥100.

    Min is willing to pay ¥10 for a hamburger. Bob is willing to sell a hamburger for $2.

    In this case, trade cannot occur.

    Maybe Alice and Min trade $2 for ¥10, and Alice buys a pair of socks instead. Or maybe Alice trades currency with 10 people like Min who buy 10 hamburgers. The products exchanged between the two countries are still of equal value.

    Alice does not have the currency to buy a ¥100 sweater unless there is demand for ¥100 worth of hamburgers.

    Altering the exchange rate doesn't help. The amount of yuan that Min is willing to pay is less than the amount of yuan that Lin is willing to accept.

    (Obviously in real life there are more than two countries. But it still must be the case that the total exports in a currency equal total imports in that currency.)

    2 AnswersEconomics2 years ago
  • What smartphone should I get?

    My iphone 4S has gotten slow enough to be pretty much unusable, so it's finally time for an upgrade.

    Are other companies as bad as Apple about planned obsolescence? I'd like a phone that will last several years and be able to handle software updates.

    All the new models are huge! I want a phone that fits in my pocket. Or comes with a belt clip or something.

    I mostly use the phone for gaming and internet. I'd like to be able to pull it out and google something without lag time. Don't need a great camera or tons of storage or fingerprint scanning.

    I'm willing to pay for quality, but I'm not willing to pay for trendiness. I'd take a Galaxy S7 over an S8 - the features look identical and the older model is that much cheaper. But again, I'd need the company to still support older models a few years from now.

    1 AnswerCell Phones & Plans2 years ago
  • Is Friday too early to buy flowers for Mother's Day?

    If I put them in water right away, will they still look good on Sunday? Or will they have already started to wilt?

    2 AnswersTrying to Conceive4 years ago
  • Choosing International investments?

    I would like to allocate part of my investments into international stocks.

    I won't be familiar with most of the companies invested in. And I don't trust an index fund to accurately represent the entire world economy.

    In the past I have tried a few mutual funds based on their past performance, but they mostly flopped. What else can I consider in order to choose a good fund?

    Or has the world market just been stuck in a rut for years so that any fund would have performed poorly?

    1 AnswerInvesting5 years ago
  • Is the Monty Hall Problem based on a real game show game?

    I first encountered the Monty Hall Problem in a book of mathematical puzzles, presented such that the answer was obviously 2/3. Supposedly, a majority of readers get that answer wrong.

    My question is not about math. My question is, what were the rules of the real game that that majority was thinking of instead of the carefully-defined puzzle that I read?

    The puzzle is named for the host of Let's Make a Deal. In the puzzle, there is a prize behind one of three doors. The contestant chooses a door, the host opens a door with nothing behind it, and the contestant has an opportunity to switch her choice to the third door.

    If this game really happened: did Monty Hall always open a door that contained nothing? Did he even know beforehand which door contained the prize?

    4 AnswersOther - Television6 years ago
  • Is it true that zero credit utilization is bad?

    I have a credit card solely for the purpose of establishing a credit history. I charge something small (maybe $30) often enough to keep the card active, and then I pay the bill in full.

    I understood that this was the best way to use a credit card, but lately I've heard that having a low credit card balance is better for your credit score than having a zero balance. Is that true? And if it is true, what's the reasoning for it?

    I can see how credit card companies might not want to extend credit to someone who won't owe them any interest. But other people looking at your credit score (car dealers, landlords, etc) should prefer to see that you're not in debt at all.

    5 AnswersCredit6 years ago
  • Centripetal force and latitude?

    Wherever you stand on the Earth, you travel in (very nearly) circular motion with a period of 1 day. This requires a centripetal force directed towards the nearest point on the Earth's axis.

    Wherever you stand on the Earth, the force of gravity is (very nearly) in the direction of the center of the Earth. NOT towards the nearest point on the axis unless you're on the equator.

    Suppose you're at 40 degrees north latitude. Gravity is at a 40 degree angle from the direction of your acceleration. The normal force from the ground is directly opposite gravity (normal to the surface). The rotation of the ground below you and air around you creates friction towards the east, tangential to the circle.

    What force adds the missing northerly component to your acceleration?

    2 AnswersPhysics8 years ago
  • Nicknames on Leverage?

    In last night's episode (the White Rabbit Job), when Sophie introduced herself as "Sally Sparrow," what did she call Hardison? Was it another Doctor Who reference?

    1 AnswerDrama8 years ago
  • How many registered voters don't have ID?

    I understand the logic of requiring ID to prevent voting fraud, and I also understand the argument that it disenfranchises anyone who doesn't have an ID.

    My question is, what are the numbers in support of the latter position? How many people would be prevented from voting because they lack a government-issued ID?

    And if anyone knows, what are the numbers on voting fraud too?

    4 AnswersElections8 years ago
  • Connection problem in modem or router?

    My setup is a cable modem (Comcast) and then a wireless-G router (Netgear).

    This has happened more than once:

    My internet connection goes out.

    I try power cycling the router, and it comes up saying it can't get an IP address from the modem.

    I try the "stand by" button on the modem. It doesn't fix the problem.

    I have to actually unplug the modem, wait for it to re-connect, and then turn on the router.

    At this point I have internet access back. But my computer's diagnostic still says "The wireless router/AP for your network is working, but your computer is not able to use an IP address to connect to the Internet."

    Comcast says there's nothing wrong with their modem, blaming it all on the router.

    What is the most likely cause for the connection loss? Is there any way to prove whether it's the modem or the router without replacing both?

    2 AnswersComputer Networking8 years ago
  • Would you keep patronizing a business that treated you badly?

    Last year, Delta Airlines delayed my flight bit by bit until finally cancelling it, and then charged me $150 to change to another flight.

    I resolved not to give them my business again. But for the trip I'm currently planning, Delta's price is more than $100 cheaper than the other airlines, AND includes one fewer layover.

    Would you take the lowest price no matter who offers it, or pay more just because it's to someone else?

    2 AnswersOther - Business & Finance8 years ago
  • If a round trip is cheaper than a one-way flight?

    Could I use the first half of a round-trip plane ticket and then cancel the return part of the flight (or just not show up)?

    Or would the airline get annoyed and charge me a penalty?

    4 AnswersAir Travel8 years ago
  • Any Avengers precursors worth seeing?

    I'm not a comic-books fan. I didn't know any backstory about the Avengers, but I saw the movie because it was written by Joss Whedon.

    Are any of the other movies about these characters as good as the new one?

    2 AnswersMovies8 years ago
  • Is a real address?

    I have an account at gmail dot com. Recently I've been getting emails written in french from a certain site (looks like a game) addressed to the same username but at

    I tried emailing the .fr address to tell that person to fix their account, and the message couldn't be delivered.

    Is a genuine email provider? Or am I just getting spammed by this site?

    1 AnswerGoogle9 years ago
  • Special relativity and acceleration?

    A rocket of rest length L starts at rest on Earth, then accelerates.

    (all measurements will be in Earth's reference frame because the rocket doesn't have an inertial frame. If you use other frames in your answer, please define them clearly)

    The fast-moving rocket is Lorentz-contracted.

    This means at any particular time, the back of the rocket has traveled further than the front of the rocket. As the rocket accelerates, this difference in distance-traveled gets shorter.

    That means the back of the rocket is moving faster than the front.

    First question: how could I calculate the Lorentz-contracted length of the rocket when it doesn't have a single speed? Knowing the length would make the next part much easier.

    Is there just one answer to how the speed/acceleration of the front and back of the rocket must be related?

    Second question:

    Suppose the front of the rocket accelerates at uniform rate a. Then at time t it has covered a distance of (1/2 a t^2) and has a speed of (at).

    If the whole rocket were moving the same speed, it would have an apparent length of L√(1-(at)^2). Since the back is moving even faster than the front, the rocket is contracted even more.

    The back of the ship has thus traveled MORE than the distance 1/2 at^2 + (L - L√(1-(at)^2).

    The front of the ship has had an average speed of at/2. The back of the ship has had an average speed of more than:

    at/2 + L (1 - √(1-(at)^2) )/t

    There's no limit to how long the rocket can be.

    For any given a and t (other than 0), I could find a value of L that makes this average speed faster than the speed of light.

    Is there a flaw in this argument?

    Or does the front of an object have a speed limit that is less than c and dependent on the object's total length?

    Third question:

    This scenario was based on a thought experiment in my textbook in which instead of a fixed acceleration the rocket had reached a "final speed" such that its length was L/2 (this speed should be √3/2). Does it make any difference to analyze the rocket after both ends have (at different times) finished accelerating?

    2 AnswersPhysics9 years ago
  • Etiquette of leaving a job?

    I've been in the same job since I graduated three years ago, and I've started looking for a change. Having never quit a job before, I am at a loss for how to go about it.

    Do I need to write a formal letter explaining why I'm leaving? Do I give it to my boss, or to HR?

    Should I start hinting now that i'm thinking about leaving, so I won't take them by surprise? Or would it be rude to make it known that I'm tired of this job, and then stick around for potentially several months?

    What else should I be doing that I haven't thought of?

    (BTW, there's nothing *wrong* with the current job. It's just getting stagnant and at entry level I know I should be learning a greater variety of skills.)

    4 AnswersOther - Careers & Employment9 years ago