Why energy must be added to a solid to cause it to melt.

According to the first law of thermodynamics, what could happen when heat is added to a system? A The internal energy of the system decreases. B The heat is turned into work done by the system. C New energy is created within the system.

The most powerful solar flare occurred in 2003. During which of the following years was the likelihood of an x-class solar flare the highest? A.) 2009, due to a maximum in the solar cycle B.) 2014, due to a maximum in the solar cycle C.

Which planet is one tenth of a distance uranus is from the sun?

When is an element most likely to be unreactive? when it loses all of its valence electrons when its valence shell is completely full when its electrons move to higher energy levels when it shares all of its valence electrons

If total (PE + KE) is considered

White moths were found in huge numbers in the city of Birmingham. These moths could be easily camouflaged by the trees. Because of sudden industrial development, the trees in the city were covered with soot.

What two factors determine how fast weathering occurs

A sound that's produced by a single wave at a constant frequency and with no overtones is called

Which of the following is ignored when determining the relative mass of atoms? protons nucleus electrons. neutrons

Gamma radiation can be significantly reduced by ... A sheet of paper Air A 3 mm thickness of aluminium Several cm of lead