A friend of yours left a pile of mail on a table. You notice your favorite magazine sticking out from under a package. You grab the magazine by its corner and get it from under the package. As you get your magazine, the package does not topple because A- it has no acceleration
B-the force of gravity keeps it secured
C-it has inertia
D- a pair of action-reaction forces act on it

The free body diagram shows a box being pulled to the left up a 25-degree incline. the magnitude of the normal force is

During the experiment if you could triple the breakaway magnetic force with all other quantities left unchanged, what is the new value for the critical velocity if it was v0 (initial velocity), initially? (b) now if you halved the radius with all other quantities left unchanged, what is the new critical velocity if it was v0 (initial velocity), initially? (c) if during the experiment, critical velocity quadrupled with all other quantities left unchanged, what is the new breakaway force if its magnitude was initially f0,?

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?