After a projectile is fired into the air, what is the acceleration in the x- direction? (Assume no air resistance.)
A. O m/s2
B. 4.9 m/s2
C. 9.8 m/s2
D. 19.6 m/s2

Which of the following is a true statement about the acceleration ~a of the pendulum bob ~a is equal to the acceleration due to gravity. ~a is perpendicular to the bob’s trajectory. ~a is equal to the instantaneous rate of change in velocity. ~a is tangent to the bob’s trajectory.