Simple multiple choice ! 1.) in the geiger-marsden experiment, a thin gold foil was bombarded by electrons alpha particles gamma rays 2.) the chemical characteristics of an atom are determined by its: atomic number mass number binding energy number of isotopes 3.) calculate the speed of the electron of a hydrogen atom if it is in the fifth circular orbit. 4.4 x 10^5 1.1 x 10^7 any is !

Astone is dropped with no initial velocity from the top of a cliff and hits the ground a time of 3.9 s later. what is the height of the cliff, in units of meters? you may assume that air resistance is negligible. give the answer as a positive number question 15 a figure skater is rotating at a rate of 200 revolutions per minute. what is the angular speed, in units of rad/s? 200 o 20.9 12000 o 3.33

Two 1.20-m nonconducting wires meet at a right angle. one segment carries + 2.50 µc of charge distributed uniformly along its length, and the other carries - 2.50 µc distributed uniformly along it, as shown in fig. 21.50. ( a. find the magnitude and direction of the electric field these wires produce at point p, which is 60.0 cm from each wire. ( b. if an electron is released at p, what are the magnitude and direction of the net force that these wires exert on it?

Explain why electric current cannot exist if a current doesn't have a voltage source.