Q:

Why do we change the clocks twice a year?

A:

The clocks change twice each year to accommodate Daylight Saving Time. In the U.S., this time period begins on the second Sunday in March and ends on the first Sunday in November.

Clocks move forward one hour in March and move backward one hour in November. Most people remember the changes with the catch phrase "spring forward, fall back," referring to the season when the changes take place. The U.S. government initially started Daylight Saving Time during World War I to save energy for wartime production. The federal government enacted Daylight Saving Time as a permanent change in 1966. Starting in 2007, the government extended the time period by four weeks as a means to save energy through longer daylight hours.


Is this answer helpful?

Similar Questions

  • Q:

    How do seasons change?

    A:

    The change in seasons is caused by the varying angle of the Earth's tilt from one part of the year to another. A common misconception is that the change in seasons is due to the Earth's slightly elliptical orbit bringing the planet closer to the sun in summer, but, as About.com notes, seasons are different in the northern hemisphere and the southern, which are the same distance from the sun.

    Full Answer >
    Filed Under:
  • Q:

    When do we turn the clocks back?

    A:

    Most Americans turn back the clock 1 hour on the first Sunday in November each year, and the official change happens at 2 a.m. This date marks the beginning of Standard Time and the end of Daylight Saving Time, which begins on the second Sunday of March.

    Full Answer >
    Filed Under:
  • Q:

    What day do we turn the clocks back?

    A:

    The date that clocks are turned back for Daylight Savings Time changes each year. In 2015, the day to turn the clocks back is Nov. 1. The day to turn the clocks forward an hour is be March 8, 2015.

    Full Answer >
    Filed Under:
  • Q:

    How do atomic clocks work?

    A:

    Atomic clocks work by exposing an atomic element to radio waves and then measuring the vibration between energy states of the atom's electrons. There are three main types of atomic clocks: cesium, rubidium and hydrogen. A second is defined as 9,192,631,770 cesium vibration cycles.

    Full Answer >
    Filed Under:

Explore