The element boron (B, atomic number 5 and atomic mass 11) is right above aluminum (Al, atomic number 13 and atomic mass 27) in the periodic table. How many more electrons does aluminum have than boron? Why?

During a lunar eclipse, during which phase of the moon can a lunar eclipse occur?

In metal wires the charged particles that move are A. protons B. electrons C. neutrons D. none of the above

What is the name for potential difference that causes current to flow?

The atmosphere is heated most by which of the following? A. Convection B. Radiation C. Wind D. Conduction

A piece of aluminum has a volume of 4.89 x 10-3 m3. The coefficient of volume expansion for aluminum is = 69 x 10-6 (C°) - 1. The temperature of this object is raised from 19.1 to 357 oC.

How big is a wifi pulse signal coming from your router? A) 10 meters B) 15 meters C) 5-10 meters D) 20-30 meters

Imagine you are in a music concert. What different sounds might you hear? How are these sounds made?

Dose aloe Vera grow in the mesa?

A tradesman sharpens a knife by pushing it against the rim of a grindstone. The 35 cm diameter stone is spinning at 200 rpm and has a mass of 28 kg. The coefficient of kinetic friction between the knife and the stone is 0.20.

What is the unit for force we use when calculating F=ma?