Life on Mars

REAL OR ILLUSION? The image has set the Internet abuzz that there really is life on Mars.

JUST LIKE US: The NASA images show a woman-like figure.

SO FAR: An arrow points towrds the woman-like figure.

London: Life on Mars? Well, bizarre images have emerged showing a mystery female figure walking down a hill on the arid planet.

The photo of what looks like a naked woman with her arm outstretched was among several taken on the red planet and sent back to Earth by NASA's Mars explorer Spirit, the Daily Mail reported on Wednesday, citing an unnamed website.

Though no official confirmation has come from NASA whether the figure is an alien or an optical illusion caused by a landscape on Mars, it has set the Internet abuzz that there really is life on Mars.

As one enthusiast put it on the website, "These pictures are amazing. I couldn't believe my eyes when I saw what appears to be a naked alien running around on Mars."

The news of the mystery woman on Mars came just days after a team of French scientists claimed to have discovered proof that the red planet possesses high-level dense clouds of dry ice, which scud across its orange sky.

Using data obtained by the OMEGA spectrometer on board ESA's Mars Express, the team found the existence of the ice clouds which sometimes become so dense that they throw quite dark shadows on the dusty surface of the red planet.

"This is the first time that carbon dioxide ice clouds on Mars have been imaged and identified from above. This is important because the images tell us not only about their shape, but also their size and density."

"Previously, we had to rely on indirect information. However, it is very difficult to separate the signals coming from the clouds, atmosphere and surface," according to lead scientist Franck Montmessin of the Service d'Aeronomie at University of Versailles.

watt-hour meters

Watt-hour meters
The utility company is not too interested in how much power you’re using with one appliance,
or even how much power a single household is drawing, at any given time. By
far the greater concern is the total energy that is used over a day, a week, a month or a
year. Electrical energy is measured in watt hours, or, more commonly for utility purposes,
in kilowatt hours (kWh). The device that indicates this is the watt-hour meter
or kilowatt-hour meter.
The most often-used means of measuring electrical energy is by using a small electric
motor device, whose speed depends on the current, and thereby on the power at a
constant voltage. The number of turns of the motor shaft, in a given length of time, is directly
proportional to the number of kilowatt hours consumed. The motor is placed at
the point where the utility wires enter the house, apartment or building. This is usually
at a point where the voltage is 234 V. This is split into some circuits with 234 V, for
heavy-duty appliances such as the oven, washer and dryer, and the general household
fines for lamps, clock radios and, television sets.
You’ve surely seen the little disk in the utility meter going around and around,
sometimes fast, other times slowly. Its speed depends on the power you’re using. The
total number of turns of this little disk, every month, determines the size of the bill you
will get—as a function also, of course, of the cost per kilowatt hour for electricity.
Kilowatt-hour meters count the number of disk turns by means of geared, rotary
drums or pointers. The drum type meter gives a direct digital readout. The pointer type
has several scales calibrated from 0 to 9 in circles, some going clockwise and others going
counterclockwise.
Reading a pointer type utility meter is a little tricky, because you must think in
whatever direction (clockwise or counterclockwise) the scale goes. An example of a
pointer type utility meter is shown in Fig. 3-11. Read from left to right. For each little
meter, take down the number that the pointer has most recently passed. Write down
the rest as you go. The meter in the figure reads 3875 kWh. If you want to be really precise,
you can say it reads 3875-1/2 kWh.

wattmeters

Wattmeters
The measurement of electrical power requires that voltage and current both be measured
simultaneously. Remember that power is the product of the voltage and current.
That is, watts (P) equals volts (E) times amperes (I), written as P
EI. In fact, watts
are sometimes called volt-amperes in a dc circuit.
You might think that you can just connect a voltmeter in parallel with a circuit,
thereby getting a reading of the voltage across it, and also hook up an ammeter in series
to get a reading of the current through the circuit, and then multiply volts times amperes
to get watts consumed by the circuit. And in fact, for practically all dc circuits,
this is an excellent way to measure power
Quite often, however, it’s simpler than that. In many cases, the voltage from the
power supply is constant and predictable. Utility power is a good example. The effective
voltage is always very close to 117 V. Although it’s ac, and not dc, power can be measured
in the same way as with dc: by means of an ammeter connected in series with the
circuit, and calibrated so that the multiplication (times 117) has already been done.
Then, rather than 1 A, the meter would show a reading of 117 W, because P
EI
117
 1
117 W. If the meter reading were 300 W, the current would be 300/117
2.56 A.
An electric iron might consume 1000 W, or a current of 1000/117
8.55 A. And a
large heating unit might gobble up 2000 W, requiring a current of 2000/117
17. 1 A. This
might blow a fuse or breaker, since these devices are often rated for only 15 A. You’ve
probably had an experience where you hooked up too many appliances to a single circuit,
blowing the fuse or breaker. The reason was that the appliances, combined, drew too
much current for the house wiring to safely handle, and the fuse or breaker, detecting the
excess current, opened the circuit.
Specialized wattmeters are necessary for the measurement of radio-frequency
(RF) power, or for peak audio power in a high-fidelity amplifier, or for certain other specialized
applications. But almost all of these meters, whatever the associated circuitry,
use simple ammeters as their indicating devices.