Sorry for not using the proper post format. I'm typing on my phone and the post template doesn't show up. Question: a box is sitting in the back of a truck which accelerates forward when a traffic light turns green. Which of the following statements is correct if the boxdoes not slip? The answer is: the force of static friction acts on the box in the forward direction. I don't understand why it's in the forward direction. I thought friction was always in the direction opposite motion, and motion, in this case, is forward. Therefore, shouldn't the friction be acting backward?