Which of the following is a completely inelastic collision? Two balls collide, stick to each other, and move together after the
collision.

Two balls collide and move at a right angle to each other after the
collision.
A ball with velocity v collides with a ball at rest; after the collision the
first ball is at rest and the second ball has velocity v.
a ball rebounds against a wall, reversing its velocity.
Two balls collide head on, each reversing its velocity.

Individuals who live below the poverty line get seriously ill more often than those who do not what could be the hidden variable in this situation?

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

Cells in the nervous system have a potential difference of 70 mv across the cell membrane separating the interior of the cell from the extracellular fluid. this potential difference is maintained by ion pumps that move charged ions across the membrane. is this an emf? select the correct answer and explanation. 1)no. the ion pumps cannot separate charges; thus, they cannot create a potential difference. 2)yes. the ion pumps cannot separate charges, but they still can create a potential difference. 3)yes. the ion pumps can actively separate charge; thus, they can create a potential difference. 4)no. the ion pumps can separate charges, but they cannot create a potential difference.