Answer:
B. Thermal energy
E. Sound energy
Explanation:
Thermal and sound energy is kinetic energy.
Kinetic energy is the energy that results as a function of the motion of a body or the particles of the medium.
Sound energy is transmitted by the vibration of the particles in the air. The vibration leads to movement of the particles and hence, kinetic energy is produced.
Thermal energy originates as a result of the temperature differences in a body. This temperature difference leads to the increase in the kinetic energy of some particles which also causes vibration and motion of the particles.
Answer:
Weight change from place to place because it is a strong function of gravity. Recall that mass is universally constant. Hence weight varies becuas gravity varies. ... Other reason for variation of weight across the earth's surface are, rotation of the earth, altitude and local topography of the area.
Answer: 270 km
Explanation:
3 cm/80 km :: 10 cm/(x)km
cross multiply
3x = 80(10)
x = 800/3 = 266.66666... ≈ 270 km
In the Periodic Table, elements with similar reactivity and similar properties are found under the same column.
In fact, elements in the same columns are said to be in the same "group", and they have the same number of valence electrons, i.e. the same number of electrons in the outermost shell. This is the main characteristics that determine how an element reacts with other elements.
For instance, Litium (Li), sodium (Na) and potassium (K) are all in the first group, and they both have 1 valence electrons. This means they can easily give away this electron to an atom of another element forming bonds with it, and therefore they have high reactivity. Instead, elements of the 8th group are called "noble gases", and they all have similar properties: they all have the outermost shell full of eletrons, so they have zero valence electrons and so they have little or no reactivity at all. Example of elements in this group are Neon (Ne) and Argon (Ar).
