pshyical change is a usually reversible change of a substance, as size or shape: Freezing a liquid is a physical change. Compare chemical change.
internal change is when the movement of the particles increases
specific latent heat is the amount of energy per kg (unit mass) required to change ice to water without change in temperature.
A). 1,000 watts = 1 kilowatt
5,000 watts = 5 kilowatts
b). (5 kilowatts) x (2 hours) = 10 kilowatt-hours (kWh)
c). (10 kWh) x (15 cents/kWh) = $1.50
you take a length of ordinary wire, make it into a big loop, and lay it between the poles of a powerful, permanent horseshoe magnet. Now if you connect the two ends of the wire to a battery, the wire will jump up briefly.When an electric current starts to creep along a wire, it creates a magnetic field all around it. If you place the wire near a permanent magnet, this temporary magnetic field interacts with the permanent magnet's field.
Mars is the focus of much scientific study about possible human colonization. Its surface conditions and the presence of water on Mars make it arguably the most hospitable of the planets in the Solar System, other than Earth. Mars requires less energy per unit mass (delta-v) to reach from Earth than any planet except Venus.
Permanent human habitation on a planetary body other than the Earth is one of science fiction's most prevalent themes. As technology has advanced, and concerns about the future of humanity on Earth have increased, the argument that space colonization is an achievable and worthwhile goal has gained momentum. Other reasons for colonizing space include economic interests, long-term scientific research best carried out by humans as opposed to robotic probes, and sheer curiosity.
One of Elon Musk's stated goals through his company SpaceX is to make such colonization possible by providing transport, and to "help humanity establish a permanent, self-sustaining colony on Mars within the next 50 to 100 years".
Many organizations support the colonization of Mars. They have also given different reasons and ways humans can live on Mars. One of the oldest organizations is the Mars Society. They promote a NASA program that supports human colonies on Mars. The Mars Society have set up Mars analog research stations in Canada and the United States. All other organizations include MarsDrive, who wants to help fund settlements on Mars, and Mars to Stay. Mars to Stay advocates settlements on Mars. In June 2012, Mars One released a statement that they believe could help start a colony on Mars by 2023.
