An alpha particle is: a hydrogen atom a nucleus of helium two neutrons an electron

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

Name the intersection of plane bpq and plane cpq.

Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.