An alpha particle (charge 2e) is sent at high speed toward an atomic nucleus. The electric force acting on the alpha particle is 79.8 N when it is 2.29 x 10(-14) m away from the nucleus. What is the charge on the atomic nucleus? (e = 1.60 x 10(-19) C, Kc = 9 x 10(9) N•m(2)/c(2)

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".