What name is given to "an object or group of objects that we wish to consider for a physics problem?

Shelly experiences a backward jolt when the driver starts the school bus. which of the following explains this phenomenon? a. the inertia of shelly b. the inertia of the bus c. the normal force of the seats on shelly d. the net force acting on shelly in a backward direction e. a zero net force acting on shelly

Along the line connecting the two charges, at what distance from the charge q1 is the total electric field from the two charges zero? express your answer in terms of some or all of the variables s, q1, q2 and k =14ï€ïµ0. if your answer is difficult to enter, consider simplifying it, as it can be made relatively simple with some work.

What determines the amount of inertia an object has