Identify the true statement. a
Action reaction pairs always act on different objects.
b
Action reaction pairs always act on the same object.
c
Non contact forces, like gravity, do not occur in action reaction pairs.
d
Contact forces, like the normal force, do not occur in action reaction pairs.

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?