Which describes how chemical changes are different from physical changes?
Select one: a. Chemical changes can be measured, but physical changes cannot. b. Chemical changes involve the formation of a new substance. c. Chemical changes release energy, but physical changes absorb energy. d. Chemical changes cannot be caused by oxygen.

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

Agas contained within a piston-cylinder assembly undergoes three processes in series: process 12: compression with pv= constant from 1 bar and 1 liter to 4 bar. process 23: constant pressure expansion to 1 liter. process 31: constant volume calculate the pressure and volume at each state, and sketch the processes on a p-vdiagram labeled with pressure and volume values at each numbered stat

Acar moves at 12m/s and coasts up a hill with a uniform acceleration of -1.6m/s2. how far has it traveled after 6.0s?