Arail gun uses electromagnetic forces to accelerate a projectile to very high velocities. the basic mechanism of acceleration is relatively simple and can be illustrated in the following example. a metal rod of mass 30.0 g and electrical resistance 0.400 ? rests on parallel horizontal rails that have negligible electric resistance. the rails are a distance l = 9.00 cm apart. (figure 1) the rails are also connected to a voltage source providing a voltage of v = 5.00 v . the rod is placed in a vertical magnetic field. the rod begins to slide when the field reaches the value b = 0.131 t . assume that the rod has a slightly flattened bottom so that it slides instead of rolling. use 9.80 m/s2 for the magnitude of the acceleration due to gravity. find the coefficient of static friction between the rod and the rails.

Did the proton move into a region of higher potential or lower potential? did the proton move into a region of higher potential or lower potential? because the proton is a negative charge and it accelerates as it travels, it must be moving from a region of higher potential to a region of lower potential.because the proton is a negative charge and it accelerates as it travels, it must be moving from a region of lower potential to a region of higher potential.because the proton is a positive charge and it slows down as it travels, it must be moving from a region of higher potential to a region of lower potential.because the proton is a positive charge and it slows down as it travels, it must be moving from a region of lower potential to a region of higher potential.request answerpart bwhat was the potential difference that stopped the proton? express your answer with the appropriate units.î”v î” v = nothingnothingrequest answerpart cwhat was the initial kinetic energy of the proton, in electron volts? express your answer in electron volts.ki k i = nothing ev request answerprovide feedback

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error

Write the function getkthdigit(n, k) that takes a possibly-negative int n and a non-negative int k, and returns the kth digit of n, starting from 0, counting from the right