## How fast can a helicopter fly?

A helicopter gets its aerodynamic lift the same way a fixed-wing aircraft does, the only difference being that it has only rotor blades instead of fixed-wings. The angle of attack (the angle at which the leading edge meets the airstream) determines the amount of lift. As the rotor turns, it traces out … Read more

## Is it true that during warm weather it is a bad idea to fill car’s petrol tank at the end of the day?

In a hurry to reach your office for a business presentation, suddenly, your car stops because you ran out of gas. You might be missing your most awaited day for your presentation; you will lose your temper and will ruin your mood on an entire day. It sucks! Running low is not … Read more

## Which has been the longest and heaviest freight train on record?

General Electric AC6000CW holds the combined record for the longest and heaviest train. On June 12, 2001, the 7.3-kilometer (4.6 miles) train traveled 275 kilometers (172 miles) in Australia, carrying 82,000 tons of ore. The train itself weighed almost 100,000 tons and hauled 682 ore cars. The GE AC6000CW was created at … Read more

## If one walks inside a train in the same direction the train is moving, does one move faster than the train?

If one walks inside a train in the same direction the train is moving, does one move faster than the train? To answer this question, we need to presume a relative point of view, since speed is a relative quantity. Let us assume the point of view of someone standing outside the … Read more

## How much CO2 does a passenger car emit per kilometer traveled?

The Answer: Carbon dioxide emissions have been an area of great scrutiny in recent years. The issue of global warming has much to do with the heat-trapping emissions caused by many parts of industry. As such, options have been put forth to help reduce the amount of carbon emissions present in our … Read more

## Why when the train races forward does its smoke go backwards?

Think of relying on coal and water yet still having sufficient energy to run over a hundred miles per hour – steam locomotives indeed are marvelous inventions. While they are no longer existing today and are replaced with more efficient trains on our railroads, steam locomotives undoubtedly left a mark in people’s … Read more

## Why do some countries drive vehicles on the left-hand side of the road while others on right-hand side?

You might have wondered why some countries drive vehicles on the left, whereas others on the right. There are several theories that help explain the concept of driving either left or right. Right-hand traffic is used in more than 165 countries, whereas 75 countries use left-hand traffic. In left-hand traffic, the steering … Read more

## Which is the longest non-stop flight ever made by a commercial airliner?

The record for making the longest non-stop flight ever by a commercial airliner is held by Boeing 777-200LR, also known as Worldliner. Mentioned in the Guinness Book of World Records, this Worldliner recorded a non-stop flight of 11,664 nautical miles – a unit of distance for airliners including the sea and land … Read more