Rutherford discovered the nucleus of the atom by firing a particles at gold foil. an a particle has a charge of q = +2e and a mass of m = 6.64-10-27 kg. a gold nucleus has charge of q-+79e. you may ignore the motion of the gold nucleus in this problem +2e +79e suppose an α particles is traveling directly toward a gold nucleus. if the speed of the a particle is u = 1.9. 107 m/s when it is 1 m from the gold nucleus, how close to the gold nucleus will the a particle come before it stops and reverses direction?

Rank the torques on the five doors shown in the figure above from least to greatest. note that the magnitude of all the forces is the same

Two friends are having a conversation. anna says a satellite in orbit is in freefall because the satellite keeps falling toward earth. tom says a satellite in orbit is not in freefall because the acceleration due to gravity is not 9.80 m/2 . who do you agree with and why?

Jason and mia are both running in a race. as they approach the finish line, you being the physicist that you are decide to time how long it takes them to reach the end of the race. when you start your stop watch (you can take this as time t = 0 s) you notice that mia is an unknown distance d ahead of jason and both are moving with the same initial velocity v_0. you also notice that jason is accelerating at a constant rate of a_j, while mia is deaccelerating at a constant rate of -a_m. jason and mia meet each other for the first time at time t = t_1. at this time (t = t_1) jason's velocity is two times that of mia's velocity, meaning v_j (t_1) = 2v_m (t_1). a) draw the position vs. time graph describing mia's and jason's motion from time t = 0 to time t = t_1. clearly label your axes and initial conditions on your graph. b) draw the velocity vs. time graph describing mia and jason's motion from time t = 0s to time t = t_1. clearly label your axes and initial conditions on your graph. c) how long from when the stop watch was started at t = 0s did it take mia and jason to meet? express your answer in terms of know quantities v_0, a_m, and a_j. d) when the stop watch started at time t = 0s, how far apart, d, were mia and jason? express your answer in terms of know quantities v_0, a_m, and a_j.