Vector a→ has a magnitude of 8 units and makes an angle of 45° with the positive x-axis. vector b→ also has a magnitude of 8 units and is directed along the negative x-axis. using graphical methods, find (a) the vector sum a→ + b→ and (b) the vector difference a→ - b→

When measuring volume, why is it important to use the correct tools and units to attain the greatest accuracy? use specific examples from the lab to support your answer. (5 points)

Consider a small frictionless puck perched at the top of a fixed sphere of radius r. if the puck is given a tiny nudge so that it begins to slide down, through what vertical height will it descend before it leaves the surface of the sphere? [hint: use conservation of energy to find the puck's speed as a func e conservation of energy to find the puck's speed as a function of its height at what value of this normal force does the puck leave the sphere? ] here on the puck.

How many electrons does each element require in its valence shell to become stable?