Grinding quartz crystals down to produce sand is an example of a
a.
change of state.
c.
chemical reaction.
b.
chemical change.
d.
physical change.

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

On a hot saturday morning while people are working inside, the air conditioner keeps the temperature inside the building at 22degreesc. at noon the air conditioner is turned off, and the people go home. the temperature outside is a constant 33degreesc for the rest of the afternoon. if the time constant for the building is 4 hr, what will be the temperature inside the building at 4 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? at 6 : 00 font size decreased by 2 upper p . font size decreased by 2 upper m .? when will the temperature inside the building reach 24degreesc? 324281

The ability to make things happen is also called a. heat b. force c. matter d. energy