Which can happen during a physical change? (2 points) select one: a. molecules can move more rapidly and freely and change states. b. the molecules in a substance break into smaller molecules. c. the molecules in a substance react with other molecules. d. the molecules in a substance are destroyed.

Aneutron and a proton combine to form a nucleus. why does the mass of the nucleus differ from the sum of the masses of the individual nucleons?

How are series and parallel circuits simililar? both have multiple paths for electrons to travel. both require resistors in their circuits. both require a switch to complete the circuit. both have at least one path for electrons to travel.

Ahanging spring stretches by 35.0 cm when an object of mass 450 g is hung on it at rest. in this situation, we define its position as x = 0. the object is pulled down an additional 18.0 cm and released from rest to oscillate without friction. what is its position x at a moment 84.4 s later? express your answer in cm.