physics please HELP !
posted by sally .
Which situations are examples of a particle with a non-zero acceleration? (Select all that are true for full credit.)
a)A car driving around a circular track at constant speed.
b)A child going back and forth on a swing
c)A runner moving in a straight line with a constant speed.
d)A car driving in a straight line and coming to a stop at a stop sign.
a,non-zero centripetal acceleration,
b,aceleration and deceleration