Exit on earth an object weighs 50 n. on planet x, the object weighs 500 n. what conclusion can be drawn from these observations? a. planet x has less mass than earth. b. earth has a greater diameter than planet x. c. the acceleration due to gravity on planet x is 98 meters per second per second. d. the acceleration due to gravity on planet x is 500 meters per second per second.

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".