An investigation was done with an electromagnetic system made from a battery and wire wrapped around a nail. different sizes of nails were used. the number of paper clips the electromagnet could pick up was measured. what is the dependent variable in this experiment? a) the size of nail used b) the amount of paperclips picked up c) the size of battery used d) the type of wire used

Aproton is projected toward a fixed nucleus of charge +ze with velocity vo. initially the two particles are very far apart. when the proton is a distance r from the nucleus its velocity has decreased to 1/2vo. how far from the nucleus will the proton be when its velocity has dropped to 1/4vo?

The midpoints? a, b, and c are marked on the histogram. match them to the indicated scores. which? scores, if? any, would be considered? unusual?

The key to stability is feedback between the reservoir and the fluxes into and/or out of the reservoir. assume that the rate of outflow from a reservoir depends on the size of the reservoir according to the following relationship: outflow rate= k x (size of reservoir), where k is a constant. a reservoir of water has a volume of 5000 liters, and the rate of outflow at steady state is 25 liters per minute. what is k? (give both the numerical value and its units.) what is the residence time? what is the relationship between k and the residence time?